-------------------------------------------------------------------------------- POPOCATÉPETL Mexico 19.02°N, 98.62°W; summit elev. 5,426 m; All times are local (= UTC - 6 hours [or 5 hours early April-late October]) Reports from 2000: | November | December | Reports from 2001: | January | February | March | April | May | June | July | August | September | October | November | December | Reports from 2002: | January | February | March | April | May | June | July | August-September | November | December | Reports from 2003: | January | February | March | April | May | June | July | August | September | November | December | Reports from 2004: | March | May | Reports from 2005: | January | February | March | Popocatépetl Activity History Information from the SI/USGS Global Volcanism Program -------------------------------------------------------------------------------- 1-7 November 2000 The Washington VAAC, Mexico MWO, and CENAPRED reported that a series of small eruptions occurred during 1715-1806 on 1 November. GOES-8 imagery showed that ash rose to between 6 and 7 km a.s.l. and extended to the NNE. The series of eruptions lasted ~30 minutes and ash fall was reported in San Pedro Nexapa and Amecameca, which is ~20 km NW of the volcano. A Reuters article reported that on 4 November the increased level of volcanism caused Mexican authorities to carefully watch for signs of a strong eruption. CENAPRED increased the Alert Level at the volcano from Yellow phase two to Yellow phase three, which expanded the high-risk zone around the volcano from 7 to 10 km. At 2048 on 6 November an eruption sent an ash cloud to an altitude of 7.5-8.5 km a.s.l. It drifted towards the N and was followed by another eruption at 2130. Ash from both eruptions fell in the town of Santiago Xalitzinta. As of 7 November the Alert Level at the volcano remained at Yellow Phase III. Sources: CENAPRED, Washington VAAC, Reuters -------------------------------------------------------------------------------- 8-14 November 2000 During the week volcanic activity was high at Popocatépetl, with several exhalations and eruptions. CENAPRED reported that exhalations at 1456 and 1541 on 7 November sent ash clouds to 2 and 4.5 km above the volcano, respectively. The Mexico City MWO reported to the Washington VAAC that an ash-and-steam exhalation at 1150 on 9 November sent ash to ~9.5 km a.s.l. According to a Reuters article, CENAPRED stated that light ashfall occurred in Santiago Xalitzintla, the closest village to the crater. The Washington VAAC reported that on 11 November eruptions at 0739, 0818, 0845, and 1418 sent ash to a maximum altitude of ~9.5 km a.s.l. The volcano's Alert Level remained at Yellow Phase III. Sources: CENAPRED, Washington VAAC, Reuters, and the Associated Press -------------------------------------------------------------------------------- 15-21 November 2000 Volcanic activity continued at a high rate at Popocatépetl, with several small-to-moderate exhalations. The Mexico City MWO and the Washington VAAC reported that at 0947 on 14 November a small ash-and-steam exhalation produced a cloud that was visible on GOES-8 imagery; it reached an altitude of ~8 km a.s.l. The cloud rapidly dissipated as it moved briefly to the NNE. At 0910 on 17 November a steam-and-possible-ash emission produced a cloud that reached up to 6.5 km a.s.l. and was blown to the NNW. The Popocatépetl camera recorded an ash cloud from a steam-and-ash exhalation that occurred at 0730 on 20 November. The cloud reached ~6 km a.s.l., was blown to the NNW, and deposited light ash in the town of San Pedro Nexapa ~10 km to the NW of the summit. On 21 November three moderate ash-and-steam exhalations sent ash to between 6 and 7 km a.s.l. The volcano's alert level remained at Yellow Phase III. Sources: CENAPRED, and the Washington VAAC -------------------------------------------------------------------------------- 22-28 November 2000 Volcanic activity continued at a high rate at Popocatépetl, with several small-to-moderate exhalations and eruptions. Remote-sensing and aviation sources provided more details. The Mexico City MWO reported to the Washington VAAC that three exhalations at 0419, 0421, and 0500 on 21 November sent ash to 5-7 km a.s.l. A pilot report and information obtained from GOES-8 imagery revealed that an eruption at 1630 on 22 November produced an ash cloud that reached between 5.5 and 7.6 km a.s.l. Subsequent imagery through 1945 that day showed that there were two ash clouds from the eruption; one rose to ~5.8 km a.s.l., and the other rose to ~7.6 km a.s.l. On 27 November eruptions at 0330 and 1815 sent ash to 6-7 km a.s.l. A pilot report stated that a small eruption occurred sometime prior to 0700 on 28 November, sending ash to ~7 km a.s.l. Sources: CENAPRED, and the Washington VAAC -------------------------------------------------------------------------------- 29 November- 5 December 2000 Volcanic activity continued at a high rate at Popocatépetl, with several small-to-moderate exhalations and eruptions. Remote-sensing data, aviation sources, and CENAPRED provided more details. One of the larger series of eruptions occurred during 0900 to 1215 on 29 November, sending ash-and-steam plumes to ~7.3 km a.s.l to the ENE. Another moderate eruption at 1055 on 30 November sent an ash cloud to ~7.3 km a.s.l. GOES-8 imagery showed that by 1815 the cloud extended at least 204 km to the ENE and traveled over the Bay of Campeche, which is ~300 km to the E of the volcano. Between 0345 and 0402 on 4 December an eruption occurred that sent ash to ~7.6 km a.s.l. Throughout the week frequent exhalations sent ash to ~6-7.6 km. Sources: CENAPRED, and the Washington VAAC -------------------------------------------------------------------------------- 6-12 December 2000 A reduction in volcanic activity at Popocatépetl led CENAPRED to reduce the Alert Level on 6 December from Yellow Phase III to Phase II, thus reducing the high-risk zone from 10 to 7 km. The Washington VAAC reported that a small steam-and-ash exhalation sent an ash cloud to ~6.7 km a.s.l. at ~2034 on 6 December. Later in the week they reported that at 1607 on 12 December a massive exhalation of ash and steam sent a cloud to ~ 8.8-10.6 km a.s.l. The ash cloud was visible on CENAPRED's Popocatépetl "Web Cam" and GOES-8 imagery. The eruption ended by approximately 1830 and by 1845 GOES-8 imagery showed that the ash cloud extended 37 km to the NE and was 14 km wide. Imagery through 2315 showed two main areas of ash; the most dense area was at an altitude of ~10.6 km a.s.l., and the other area was between 4.9 and 5.5 km a.s.l. The local airport was alerted to the eruption and as of 12 December the volcano remained at Alert Level Yellow Phase II. Sources: CENAPRED, Washington VAAC, and Notimex -------------------------------------------------------------------------------- 13-19 December 2000 For the first time in 6 years, continuous-fountaining Strombolian-style eruptions of incandescent spatter occurred at Popocatépetl, marking a significant change in eruption behavior. In addition, strong harmonic tremor and high-mass flux rates have occurred. As of the end of the report period, the summit crater contained hot lava, and continuous ash emissions deposited ash in several towns surrounding the volcano. This report is updated weekly but volcanic activity can change rapidly. To obtain more up-to-date volcanic activity reports refer to the CENAPRED website and/or contact their hotline at 01-800-123-5050. In addition, the Washington VAAC website provides detailed accounts of ash-producing volcanic activity. Since the large exhalation on 12 December sent ash to an altitude of ~10.6 km a.s.l., continuous ash emissions have occurred, with occasional large exhalations of ash reaching a maximum altitude of ~11 km a.s.l. High levels of seismic activity, including harmonic tremor, and other monitoring parameters led officials to raise the Alert Level at the volcano on 16 December from Yellow Phase II to Phase III, thus increasing the high-risk zone from 7 to 10 km. In addition, according to a Reuters article, officials called on ~30,000 residents living within a ~12-km-radius around the volcano to evacuate to 180 refugee centers. On 16 December CENAPRED scientists flew over the volcano and found that a new lava dome had formed in the crater. The Washington VAAC reported that an eruption involving lava began at 1915 on 18 December, sending an ash cloud to an altitude of ~7.3 km a.s.l. In addition, the eruption sent incandescent spatter 1 to 2 km SE of the volcano. CENAPRED reported that during 18 and 19 December a large increase in volcanic activity occurred, consisting mainly of Strombolian ejections. According to a Reuters article, there were concerns that a ~900-km-long glacier on the volcano's western face could be melted by lava and produce lahars. This led officials to extend the high-risk zone to ~20 km. Interior Minister Santiago Creel told a news conference on 19 December, "We are on maximum alert ... because we have to be ready for any possible contingency regarding the glacier." As of 20 December (the end of the report period) continuous ash emissions were occurring and a very large ash cloud covered a large portion of S Mexico, extended E across the southern Gulf of Mexico and to near the N tip of the Yucantan Penninsula. Sources: CENAPRED, Washington VAAC, Reuters 1, Reuters 2, Associated Press, and Stromboli On-Line -------------------------------------------------------------------------------- 20-26 December 2000 Volcanic activity at Popocatépetl decreased in comparison to last week. The Washington VAAC reported that during 21 to 25 December there were intermittent emissions of mostly steam. In addition, several small-to-moderate explosive events occurred during the week; at 1555 on 24 December ash was erupted to ~9 km a.s.l. and then blown to the E; at 1045 on 25 December ash was erupted to between 5.5 and 7.6 km a.s.l., blown to the NE, and deposited less than 5 km from the summit; and moderate exhalations occurred at 0111 and 0631 on 27 December that sent ash up to 7.6 and 9.8 km, respectively. On 26 December CENAPRED reported that beginning on 24 December the volcano entered a new phase of activity. Moderate explosions were expected to continue for several days or weeks until the lava dome in the summit crater is destroyed. CENAPRED scientists determined that there was decreased likelihood of a large eruption. Most of the 41,000 residents near the volcano, who were evacuated beginning on 15 December, were permitted to return to their homes. The evacuees were warned to remain alert for further activity. The director of CENAPRED, Robert Quaas, told journalists at a press conference on 26 December that, "The volcano could continue to launch incandescent fragments as far as 5 km and could provoke a moderate rain of cooled fragments as far away as 10 km, because of events related to the destruction of the lava dome." The volcano remained at Alert Level Yellow Phase III, but the restricted area was reduced from 13 to 12 km. For more information about the present state of the volcano and the return of evacuees to their homes refer to CENAPRED's 26 December Bulletin. Sources: CENAPRED, Washington VAAC, Reuters, Associated Press, and Notimex -------------------------------------------------------------------------------- 27 December 2000- 2 January 2001 CENAPRED reported that low-intensity exhalations occurred during most of the week. At 1118 on 30 December an intense seismic signal was recorded for 4 minutes that was characteristic of exhalations with explosive initial phases. At 1955 on 30 December a pilot report stated that an eruption sent an ash cloud to 8.5 km a.s.l. CENAPRED received reports that ash fell in the towns of Huejotzingo (~30 km to the NE of the volcano), San Pedro (~10 km to the SE), Cholula (~35 km to the E) and Puebla (~50 km to the E). GOES-8 imagery showed that ash from the eruption dissipated by 0100 on 31 December. Exhalations also occurred at 0507 on 31 December and at 0936 on 2 January, and sent ash clouds to 8.5 and 7.6 km, respectively. Sources: CENAPRED, Washington VAAC, Reuters 1, Associated Press and Reuters 2 -------------------------------------------------------------------------------- 3-9 January 2001 CENAPRED reported that low-level activity continued at Popocatépetl. The Washington VAAC remotely detected two exhalations on GOES-8 imagery during the week; at 1300 on 4 January a small eruption sent ash to ~7.3 km a.s.l. that blew to the E, and at 0655 on 8 January a brief ash-and-steam emission sent a cloud to ~6 km a.s.l. that blew to the E. The volcano remained at Alert Level Yellow Phase III, with a 12-km-radius restricted area. Sources: CENAPRED and the Washington VAAC -------------------------------------------------------------------------------- 17-23 January 2001 In addition to multiple exhalations, Popocatépetl produced both pyroclastic flows and mudflows that traveled several kilometers downslope. The Washington VAAC reported that at ~1500 on 14 January a small exhalation sent ash to ~7.6 km a.s.l. They also reported that a larger explosive eruption occurred at ~1615 on 22 January that sent ash to 6-12 km a.s.l. CENAPRED reported that the eruption produced pyroclastic flows that descended ~4-6 km down several gorges on the N and NW flanks of the volcano. Ash was deposited on Santiago Xalitzintla, Atlixco, Tecamachalco, Tetela, and part of Puebla. A small (10 cm thick and 2 m wide) mudflow traveled up to 8 km from the town of Santiago Xalitzintla down the Huiloac gorge. Scientists believe the pyroclastic flows melted a small portion of the glacier near the volcano's summit and the glacial meltwater mixed with ash. Another explosive eruption that occurred at 1915 the same day was followed by ongoing ash exhalations through 23 January. An eruption at 1041 on 23 January sent ash to ~9.1 km a.s.l. that blew to the S. Several small explosions and continuous ash emissions followed. The volcano remained at Alert Level Yellow Phase III with a 12 km security radius. Sources: CENAPRED and the Washington VAAC -------------------------------------------------------------------------------- 24-30 January 2001 During the week several small-to-moderate sized eruptions occurred, with light ashfall reported in two towns and a pyroclastic flow stopping 8 km short of a town. The Washington VAAC reported that on 25 January an ash plume, which was produced by rockfall activity, rose to ~7 km a.s.l and was visible on GOES-8 imagery. According to CENAPRED, at 1338 on the same day an exhalation produced an ash cloud that rose to 3 km above the volcano and blew to the NW, depositing ash in San Pedro Nexapa, ~15 away. A minor eruption at 1212 on 27 January produced an ash cloud that rose to 6.4 km a.s.l. and blew to the NE, depositing light ash in the town of Santiago Xalitzintla, ~15 km from the volcano. An ash-and-steam eruption at 1155 on 28 January produced an ash cloud that that rose to 7 km and blew to the NE. Based on information from the Mexico City MWO, the Washington VAAC reported that an eruption occurred at 1104 on 29 January. A pilot report stated that the ash cloud from the eruption rose to ~11.9 km a.s.l., while CENAPRED reported that the cloud rose to ~8 km a.s.l. and blew to the NE. The eruption sent pyroclasts out to 1 km from the crater and produced pyroclastic flows that traveled down the NE flank of the volcano, stopping 8 km before reaching the town of Santiago Xalitzintla. The pyroclastic flows caused some melting of the summit glacier located primarily on the upper N and W flanks. The volcano remained at Alert Level Yellow Phase III, with a 12-km-radius restricted area. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC, Associated Press -------------------------------------------------------------------------------- 31 January- 6 February 2001 The Washington VAAC reported that during 1530 to 1545 on 30 January a moderate ash emission was visible on the CENAPRED camera; it rose to ~7 km a.s.l. and blew to the NNE. At 1345 on 1 February a small eruption was visible on GOES-8 imagery. The narrow plume of ash rose to ~6.7 km and blew to the NNE. The volcano remained at Alert Level Yellow Phase III, with a restricted area of 12-km-radius. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 7-13 February 2001 The Washington VAAC reported several small ash-bearing eruptions during the week. At 1921 on 8 February an eruption produced a small ash cloud that rose up to ~7.6 km a.s.l. and blew to the NE. At 1400 on 9 February an eruption produced an ash cloud that rose up to ~6.7 km. A small ash plume produced from emissions that occurred at 1338 and 1348 on 11 February was visible in GOES-8 imagery. The ash plume rose up to ~7.9 km a.s.l. and blew to the S. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 14-20 February 2001 The Washington VAAC reported that an eruption occurred at 1642 on 15 February, producing an ash cloud that rose up to 7.9 km a.s.l. and drifted to the ENE. The cloud was visible on GOES-8 imagery and by 1802 it had traveled to the Gulf of Mexico. The volcano remained at Alert Level Yellow Phase III, with a restricted area of 12-km-radius. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 21-27 February 2001 CENAPRED reported that small exhalations occurred at Popocatépetl during the week. The Washington VAAC did not report that ash was visible in satellite imagery. The volcano remained at Alert Level Yellow Phase III, with a restricted area of 12-km-radius. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 28 February- 6 March 2001 CENAPRED reported that activity remained relatively low at Popocatépetl during the week, with small exhalations accompanied by steam emissions. The volcano remained at Alert Level Yellow Phase III, with a restricted area of 12-km-radius. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 7-13 March 2001 CENAPRED reported that Popocatépetl's activity was at low-to-moderate levels during most of the week, with small exhalations accompanied by steam emissions. Based on reports from the Mexico MWO, the Washington VAAC reported that at 2024 on 12 March an ash cloud from an exhalation of Popocatépetl was observed at a height of ~ 7 km a.s.l. The ash cloud was not visible on GOES-8 imagery. The volcano remained at Alert Level Yellow Phase III, with a restricted area of 12-km-radius. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 14-20 March 2001 According to CENAPRED, volcanic activity that was relatively high during 14-16 March began to diminish on 17 March. On 14 and 15 March there were many small exhalations of steam, ash, and gas, as well as episodes of harmonic tremor that totaled 1 hour. On 15 March a new lava dome ~200 m in diameter and 40 m high was observed at the volcano's summit. By 17 March fewer exhalations occurred than on previous days and harmonic tremor was only detected for a total of 15 minutes. The volcano remained at Alert Level Yellow Phase III, with a restricted 12-km-radius area. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 21-27 March 2001 According to CENAPRED, volcanic activity remained low and relatively unchanged throughout 22-27 March. Low-intensity steam-and-gas exhalations continued, sometimes with small amounts of ash. Spoardic episodes of harmonic tremor were reported on most days, with the longest episode lasting 1.5 hours on the evening of 24 March. The volcano remained at Alert Level Yellow Phase III, with a restricted 12-km-radius area. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 28 March- 3 April 2001 CENAPRED reported that volcanic activity continued at Popocatépetl, with several small exhalations and moderate seismic activity. The volcano remained at Alert Level Yellow Phase III, with a restricted 12-km-radius area. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 4-10 April 2001 The CENAPRED reported that during the previous two weeks activity increased at Popocatépetl. Seismographs detected episodes of harmonic tremor totaling up to 8 hours per day, two tectono-volcanic earthquakes per day with magnitudes up to 2.3, and high-frequency tremor. This activity is related to the emplacement of a new lava dome, which was first observed on 14 March, that could produce explosive activity. The volcano remained at Alert Level Yellow Phase III, with a restricted 12-km-radius area. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 11-17 April 2001 Several small-to-moderate exhalations occurred during the week at Popocatéptl. CENAPRED reported that at 1948 on 16 April a moderate explosion sent incandescent fragments up to 2 km away from the volcano's crater to the NE and NW and produced an ash plume that rose 4 km above the crater and drifted to the SW. The 40-second-long eruption partially destroyed the lava dome that had formed within the crater over the course of several weeks. The volcano remained at Alert Level Yellow Phase III, with a restricted 12-km-radius area. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC, Associated Press -------------------------------------------------------------------------------- 18-24 April 2001 Small-to-moderate exhalations continued at Popocatépetl. On 17 April a small lahar traveled down the Achupashal Gorge. The volcano remained at Alert Level Yellow Phase III, with a restricted 12-km-radius area. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC, Associated Press -------------------------------------------------------------------------------- 25 April- 1 May 2001 CENAPRED reported that at 0819 on 29 April a moderate explosion occurred at Popocatépetl that lasted for 1 minute and produced an ash cloud that rose 2 km above the volcano's summit and drifted to the ENE. A pilot reported that the ash cloud reached an altitude of 9 km a.s.l. Light ash fall was reported in San Pedro Benito Juárez ~10 km SE of the volcano's summit. Throughout the day several episodes of harmonic tremor occurred. Based on information from the Mexico City MWO, the Washington VAAC reported that another eruption occurred later the same day at 1310. It produced an ash cloud that rose 6.7-7.6 km a.s.l. The volcano remained at Alert Level Yellow Phase III, with a restricted 12-km-radius area. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC, Associated Press -------------------------------------------------------------------------------- 2-8 May 2001 Several small exhalations at Popocatépetl produced small plumes of steam and ash with the largest plume rising up to 1.5 km above the crater. The volcano remained at Alert Level Yellow Phase III, with a restricted 12-km-radius area. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC, Associated Press -------------------------------------------------------------------------------- 9-15 May 2001 CENAPRED reported that at 2301 on 13 May a small explosion sent incandescent fragments as far away as 0.5 km from the crater. At 0939 on 14 May an ash-and-steam plume rose 1.5 km above the crater. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 16-22 May 2001 Small-to-moderate sized exhalations consisting mostly of gas and steam occurred at Popocatépetl during the week. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 23-29 May 2001 Small-to-moderate sized exhalations occurred during the week. Based on information from the Mexico City MWO, the Washington VAAC reported that an eruption occurred on 26 May at 1122 that sent a steam-and-ash plume up to ~7 km a.s.l. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 30 May- 5 June 2001 CENAPRED reported that on 31 May at 2136 a moderate-sized eruption began with the most intense phase lasting ~1 minute. Incandescent material traveled 2-3 km down the NE flank of the volcano. According to the Mexico City MWO a steam-and-ash cloud was observed rising up to 7.6 km a.s.l. and drifting to the W. A smaller eruption occurred on 1 June at 0804 that sent a steam-and-ash cloud up to 7 km a.s.l. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 6-12 June 2001 Activity during 6-7 June remained at normal low levels, with minor gas-and-steam emissions, tremor, and a few small volcano-tectonic earthquakes at around 6 km depth below the crater. Increased emissions on 8 June sometimes included small amounts of ash. An explosion on 9 June at 0424 sent ash to an unknown height. Moderate activity continued through the next morning and decreased slightly. The Mexico City MWO reported an ash emission on 11 June at 1100 that rose 7.6 km a.s.l., but it was not seen on satellite imagery. The MWO warned of another ash emission on 12 June at 1648, but cloudy conditions prevented a height estimate. Typical low-to-moderate activity continued through 13 June, with the Yellow alert level unchanged. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 13-19 June 2001 Volcanic activity at Popocatépetl remained at normal levels, with several small exhalations of steam, gas, and small amounts of ash. The volcano remained at Alert Level Yellow Phase III, with a restricted 12-km-radius area. Sources: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 20-26 June 2001 Volcanic activity at Popocatépetl remained at normal levels, with several small exhalations of steam, gas, and small amounts of ash. Based on information from CENAPRED, the Washington VAAC reported that on 24 June at 0900 a small eruption produced an ash cloud that rose ~0.5 km above the volcano and drifted to the SW. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 27 June- 3 July 2001 Volcanic activity at Popocatépetl remained at normal levels, with several small exhalations of steam, gas, and small amounts of ash. Based on information from the Mexico City MWO, the Washington VAAC stated that on 1 July at 0915 a small eruption produced an ash plume that rose to less than 1 km above the volcano and drifted to the SSW. On 3 July at 0425 a moderate-sized exhalation produced an ash cloud seen on satellite imagery to spread in two directions; to less than 1 km above the volcano drifting to the NW, and ~4 km above the volcano drifting to the SE. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 4-10 July 2001 On 3 July at 0410 and 0648 moderate-sized explosions occurred. The latter explosion lasted about 10 minutes and produced an ash cloud that rose ~4 km above the volcano. Initially the cloud drifted to the SE and later the highest portion of the cloud drifted to the NW. Based on information from pilot reports and ground observations, the Washington VAAC reported that the ash cloud was 9.3 km SE of Mexico City Airport at 0930. Ashfall occurred in several towns including Chalco, ~35 km NW of the volcano, and there were reports of light ashfall on the airport's runways. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC, Associated Press, CNN -------------------------------------------------------------------------------- 11-17 July 2001 Several small-to-moderate sized emissions occurred at Popocatépetl, including three on 14 July. According to the Washington VAAC, around 1045 an emission of steam, gas, and small amounts of ash rose to ~7.3 km a.s.l. and drifted to the W. Emissions also occurred at 2303 and 2341. A cloud from the latter emission rose to ~6.1 km a.s.l. and drifted to the W. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC, Associated Press -------------------------------------------------------------------------------- 18-24 July 2001 Several small-to-moderate sized emissions occurred at Popocatépetl that were mainly composed of steam, gas, and small amounts of ash. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 25-31 July 2001 Several small-to-moderate sized emissions occurred at Popocatépetl that were mainly composed of steam, gas, and small amounts of ash. The Washington VAAC received a pilot report on 24 July at 1100 of an ash cloud ~5.5 km above the volcano drifting to the W. On 23 July CENAPRED reduced the Alert Level from Yellow Phase III to Phase II because volcanic activity was at lower levels than it was in December 2000 when the Alert Level was originally raised. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 1-7 August 2001 Low-level volcanic activity occurred at Popocatépetl during the week. Several small emissions occurred at the volcano that were mainly composed of steam, gas, and small amounts of ash. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 8-14 August 2001 The number of small emissions composed of steam, gas, and small amounts of ash increased in comparison to the previous week. The Washington VAAC reported an ash emission on 9 August at 2300 produced an ash cloud that rose to 7.6 km a.s.l. According to CENAPRED, the increase in activity may have been related to several days of intense rain in the area. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 15-21 August 2001 Small emissions of steam, gas, and small amounts of ash continued at Popocatépetl. The Mexico City MWO reported that on 17 August at 1514 an ash emission produced a cloud that rose to 7.3 km a.s.l. The Washington VAAC reported that GOES-8 satellite imagery did not show an ash plume, but did show an occasional hotspot. CENAPRED reported that recent activity was related to the growth of a new lava dome inside the crater. The volcano remained at Alert Level Yellow Phase II. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 22-28 August 2001 Volcanic activity remained relatively low at Popocatépetl, with small emissions of steam, gas, and minor amounts of ash. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 29 August- 4 September 2001 Volcanic activity remained relatively low at Popocatépetl, with small emissions of steam, gas, and minor amounts of ash. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 5-11 September 2001 On 9 September at about 0815 an episode of frequent moderate-sized eruptions began at Popocatépetl. The eruptions produced steam-and-ash emissions that rose to a maximum height of 1 km above the crater and drifted to the NW. During the night a small explosion sent incandescent fragments up to 200 m from the crater. Eruptive activity continued through at least 1230 on 9 September. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 12-18 September 2001 During the week, volcanic activity at Popocatépetl consisted of small emissions of steam, gas, and minor amounts of ash. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 19-25 September 2001 During the week, volcanic activity at Popocatépetl consisted of small emissions of steam, gas, and minor amounts of ash, and episodes of harmonic tremor. Analysis of aerial photographs taken on 20 September revealed that the lava dome had continued to grow since it was first observed on 10 August. The dome is growing inside the inner crater, which formed within the summit crater after a dome was destroyed in December 2000. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 26 September- 2 October 2001 During the week, volcanic activity at Popocatépetl consisted of small emissions of steam, gas, and minor amounts of ash, and episodes of harmonic tremor. Pilots reported that a steam emission rose 4 km above the volcano on 26 September at 1000. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 3-9 October 2001 During the week, Popocatépetl emitted small clouds of steam, gas, and minor amounts of ash, and underwent episodes of harmonic tremor. According to reports from the México City MWO to the Washington VAAC, a small eruption on 9 October at 0712 produced an ash cloud that rose 2 km above the volcano and drifted to the W. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 10-16 October 2001 During the week, Popocatépetl emitted small clouds of steam, gas, and minor amounts of ash, and underwent episodes of harmonic tremor. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 17-23 October 2001 During the week, Popocatépetl emitted small clouds of steam, gas, and minor amounts of ash. In addition, seismometers recorded episodes of harmonic tremor. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 24-30 October 2001 On 25 October at approximately 0600 a steam column was observed rising 1-2.5 km above Popocatépetl's crater, drifting to the NW. Ground observations confirmed that the column did not include ash. The MWO reported to the Washington VAAC that another eruption column the same day at 1040 rose to ~6.7 km. A narrow plume of ash from the eruption was visible extending to the N on satellite imagery. The volcano remained at Alert Level Yellow Phase II. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 31 October- 6 November 2001 Volcanic activity remained low at Popocatépetl, with emissions of small clouds of steam, gas, and minor amounts of ash. Episodes of low-amplitude harmonic tremor also occurred. An aerial photograph of the crater was taken on 25 October by the Dirección General de Carreteras Federales, SCT. It showed that the lava dome, which was first reported on 20 September 2001, had subsided. In addition, a new, small 50-m-diameter lava dome had grown in the bottom of the internal crater. According to CENAPRED, a similar situation had been observed in April 2001 and the presence of the lava dome indicates the possibility of small explosions occurring in the next days to weeks. The volcano remained at Alert Level Yellow Phase II. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 7-13 November 2001 On 10 November at 0324 a small explosive event produced an ash column that rose 1 km above Popocatépetl's summit and drifted to the E. CENAPRED's volcano camera showed incandescent fragments hurled up to 300 m E. During the rest of the week, volcanic activity at Popocatépetl remained low, with emissions of small clouds of steam, gas, and minor amounts of ash. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 14-20 November 2001 During the week, Popocatépetl emitted small clouds of steam, gas, and minor amounts of ash. There were episodes of increased emissions and seismometers recorded periods of harmonic tremor. According to CENAPRED, this type of activity may be associated with lava dome growth, as occurred on 15 August and 10 September 2001. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 21-27 November 2001 During the week, Popocatépetl emitted small clouds of steam, gas, and minor amounts of ash. In addition, episodes of harmonic tremor were recorded. During a flight over the volcano on 21 November observers noticed a new 130-m-diameter lava dome growing inside the internal crater. The growth of this lava dome corresponded with increased emissions and seismicity on 17 and 18 November. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 28 November- 4 December 2001 During the week, Popocatépetl emitted small clouds of steam, gas, and minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 5-11 December 2001 On 10 December at 1830 an increase in activity began at Popocatépetl. There were more ash emissions at the volcano than in comparison to the previous weeks. Several small-to-moderate emissions ejected incandescent fragments about 1 km around the volcano. The strongest activity occurred during 2000 to 2200. Following the increased activity only sporadic emissions occurred. The Washington VAAC reported that ash clouds rose less than 1 km above the volcano and drifted to the ENE. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 12-18 December 2001 During the week, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. The highest reported ash cloud was produced from an eruption on 17 December at 2213. It rose 7.3 km a.s.l. and drifted to the SW. CENAPRED reported that a new 190-m-diameter lava dome in the volcano's crater was observed on 11 December. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 19-25 December 2001 A period of lava-dome destruction and possible new dome growth during 18 to at least 26 December included several explosions and episodes of harmonic tremor. During a 3-minute-long eruption on 19 December starting at 1926, volcanic fragments were hurled 2 km to the E and NE. In addition, an ash cloud was probably produced, but was obscured by meteorological clouds. Another notable explosion, on 22 December at 1735, produced an ash cloud that rose 2.5 km above the volcano and drifted to the NE. After this event a small amount of ash fell in the town of Puebla, ~50 km E of the volcano. By 23 December volcanic activity decreased, with fewer eruptions, less fumarolic activity, and short episodes of high-frequency tremor. According to CENAPRED, the activity during the week was related to destruction of the lava dome first seen on 21 November 2001. They warned that similar activity may occur in the following days or weeks. The volcano remained at Alert Level Yellow Phase II. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC, Associated Press -------------------------------------------------------------------------------- 26 December 2001 - 1 January 2002 During the week, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. The highest reported ash cloud was produced from an eruption on 29 December at 0432 and rose 5.5-8.8 km a.s.l. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 2-8 January 2002 During the week, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. On 7 January at 1330 a small ash emission was visible on satellite imagery at a height of 7.6 km a.s.l. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 9-15 January 2002 During the week, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. The highest reported volcanic cloud, from an eruption on 13 January at 1709, reached a height of ~7.3 km and drifted to the ENE. A photograph of Popocatépetl 's summit area taken on 11 January confirmed that the lava dome reported in December 2001 had been partially destroyed. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 16-22 January 2002 During the week of 16-22 January, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres, -------------------------------------------------------------------------------- 23-29 January 2002 According to CENAPRED, on 23 January at 0517 a moderate eruption began at Popocatépetl. It was accompanied by continuous tremor. Incandescent volcanic fragments were ejected short distances from the crater, and a steam-and-ash cloud was produced. According to pilot reports, the cloud rose to ~9 km a.s.l. Satellite imagery showed that the cloud drifted to the NE; by 1845 it was visible near the city of Poza Rica, ~250 km to the NE. The cloud continued drifting NE and travelled over the Gulf of Mexico. Small amounts of ash fell in Paso de Cortés and the town of Tlaxcala. CENAPRED reported that the activity was related to the formation of a new lava dome. Following the 23 January eruption, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 30 January-5 February 2002 Air photos taken on 24 January revealed that the new lava dome growing in Popocatépetl's summit crater was 180 m in diameter and 150 m high. During 30 January-5 February Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 6-12 February 2002 During the week, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 13-19 February 2002 Seismicity increased slightly at Popocatépetl during 15-16 February after several weeks of low activity. Harmonic tremor and low-magnitude volcanotectonic micro-earthquakes were recorded. During the same period emissions of gas, steam, and some ash occurred. CENAPRED stated that the activity was possibly related to the ascent of magma and the formation of a new lava dome. They added that this activity could lead to explosions in the next days to weeks. The volcano remained at Alert Level Yellow Phase II. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 20-26 February 2002 On 19 February frequent small-to-moderate emissions of steam, gas, and minor amounts of ash occurred at Popocatépetl. In addition, small explosions occasionally threw incandescent volcanic fragments short distances from the crater. During 0750-0900 small amounts of ash fell in Paso de Cortés. Also, isolated episodes of harmonic tremor were registered. On 23 February at 2156 a small explosion threw incandescent fragments up to 200 m that fell within the crater and a low-volume ash column rose 700 m above the crater and drifted to the W. Later, isolated harmonic tremor was detected. According to CENAPRED, the activity on the 19th and 23rd was related to the partial destruction of the lava dome in the crater and low-level explosive activity was considered possible in the next days or weeks. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 27 February-5 March 2002 During 28 February-5 March, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. According to CENAPRED, volcanic and seismic activity during the report period was probably related to a new episode of lava-dome growth. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 6-12 March 2002 During 6-11 March, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. On 9 March a steam-and-gas emission rose to ~2 km above the crater. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 13-19 March 2002 During 6-11 March, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 20-26 March 2002 During 20-26 March, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 27 March-2 April 2002 During 27 March-2 April, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Based on information from the Mexico City MWO, the Washington VAAC reported that on 26 March at 2132 seismicity suggested that an emission may have occurred. Extensive cloud cover precluded the detection of ash on satellite imagery. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 3-9 April 2002 During 3-9 April, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. A moderate explosion on 8 April at 0438 produced an ash cloud to a height of ~7.6 km a.s.l. Incandescence was visible at the volcano during the eruption. A small ash cloud was visible on satellite imagery drifting to the E and by 1145 the cloud had drifted over the coast of México near the city of Veracruz. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 10-16 April 2002 During 10-15 April, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 17-23 April 2002 During 17-23 April, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Sources: Centro Nacionale de Prevencion de Desastres, Associated Press -------------------------------------------------------------------------------- 24-30 April 2002 During 24-30 April, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. On 29 April at 2232 an eruption produced an ash cloud to a height of 1.5 km and sent incandescent fragments 500 m from the crater. No ash was visible on satellite imagery. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 1-7 May 2002 During 1-7 May, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 8-14 May 2002 During 8-12 May, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. A small explosion on 12 May at 0609 hurled incandescent pyroclasts less than 500 m down the volcano's N flank. Aerial photography taken on 29 April by the Department of Federal Roads and the Ministry of Communication and Transportation revealed a 170-m-diameter lava dome growing in the crater. According to CENAPRED, recent volcanic and seismic activity at Popocatépetl has been related to the growth of this lava dome. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 15-21 May 2002 During 15-21 May, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 22-28 May 2002 During 21-28 May, Popocatépetl emitted small clouds of steam, gas, and generally minor amounts of ash. In addition, episodes of harmonic tremor were recorded. On 21 May at 1330 a small explosion occurred that was followed by 15 minutes of high-frequency tremor. According to a news report, a small amount of ash fell on communities neighboring the volcano on 22 May. Sources: Centro Nacionale de Prevencion de Desastres, Associated Press -------------------------------------------------------------------------------- 29 May-4 June 2002 During 29 May-4 June, seismic and volcanic activity were relatively low at Popocatépetl. Activity mainly consisted of small steam-and-gas emissions. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 5-11 June 2002 During 5-11 June, seismic and volcanic activity were relatively low at Popocatépetl. Activity mainly consisted of small steam-and-gas emissions. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 12-18 June 2002 During 12-18 June, activity at Popocatépetl mainly consisted of small steam-and-gas emissions. A photograph of the lava dome taken on 22 May revealed that it had diminished in size compared to 29 April. Based on information from ground reports, video footage, and MWO, the Washington VAAC reported that an eruption occurred on 17 June at 1140. An ash cloud was produced that rose to a height of ~8 km a.s.l. and drifted to the WSW. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 19-25 June 2002 During 18-24 June, activity at Popocatépetl mainly consisted of small steam-and-gas emissions. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 26 June-2 July 2002 During 26 June-1 July, there were small-to-moderate emissions of steam, gas, and ash at Popocatépetl. In addition, several episodes of low-amplitude harmonic tremor were recorded. The most notable emissions, on 26 June at 1110 and on 1 July at 0238, produced ash clouds to a height of ~2 km above the volcano. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 3-9 July 2002 During 2-7 July, there were small-to-moderate emissions of steam, gas, and ash at Popocatépetl. In addition, several episodes of low-amplitude harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 10-16 July 2002 During 8-15 July, there were small-to-moderate emissions of steam, gas, and ash at Popocatépetl. In addition, several episodes of low-amplitude harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 17-23 July 2002 During 17-22 July, there were small-to-moderate emissions of steam, gas, and ash at Popocatépetl. In addition, several episodes of low-amplitude harmonic tremor were recorded. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 24-30 July 2002 During 23-30 July, there were small-to-moderate emissions of steam, gas, and ash at Popocatépetl. Based on information from the Mexico City MWO, the Washington VAAC reported that on 26 July an ash cloud rose 5.5-6.7 km a.s.l. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 28 August-3 September 2002 In August there were several emissions of steam, gas, and minor amounts of ash at Popocatépetl. In addition, episodes of both harmonic and high-frequency tremor occurred. CENAPRED attributes this activity to a new lava dome that has been growing for several weeks. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 6-12 November 2002 A moderate eruption occurred at Popocatépetl on 6 November at 0735. According to aircraft reports, the eruption produced a small amount of ash that reached 4 km above the crater and drifted slightly to the N. An intense 3-minute-long phase was followed by high-frequency tremor. Minor ashfall occurred in towns including San Juan Tehuixtitlán, San Pedro Nexapa, Amecameca, Ecatzingo,Tepejomulco, Ozumba, and San Vicente Chimalhuacán. Four small eruptions also occurred during the day. The Alert Level remained at Yellow Phase II, with a restricted area of 12 km from the crater. Source: Centro Nacionale de Prevencion de Desastres, Associated Press -------------------------------------------------------------------------------- 11-17 December 2002 During December there were several emissions of steam, gas, and minor amounts of ash at Popocatépetl. According to CENAPRED, new episodes of low-frequency tremor, beginning on 19 November, signaled the growth of a new lava dome within Popocatépetl's crater. Aerial photographs obtained by the Mexican Ministry of Communications and Transportation on 2 December confirmed the presence of a fresh lava dome measuring about 180 m in diameter at its base, and about 52 m high. The lava dome grew in episodes of variable duration, at a mean extrusion rate of 8-9 m3 per second. These dome-growth episodes were distinctly recorded by the monitoring network as harmonic tremor. Small associated inflation was also recorded. CENAPRED stated that dome growth may continue and could conclude with dome-destruction episodes, which have occurred in the past. The Alert Level at Popocatépetl remained at Yellow. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 18-23 December 2002 Moderate explosions occurred at Popocatépetl on 18 December. After a period of high-frequency tremor, an explosion occurred at 0148 that produced an ash cloud that reached 2 km above the crater. Later, at 0209 and 0214 two explosions sent ash to ~0.5 km above the crater. that drifted to the NE. Fragments were sent around the crater a distance of ~1.5 km. The volcano returned to its previous relatively low level of activity. Popocatépetl remained at Alert Level Yellow phase II. Source: Centro Nacionale de Prevencion de Desastres, Washington VAAC, EFE via COMTEX -------------------------------------------------------------------------------- 24-30 December 2002 A moderate explosion occurred at Popocatépetl on 23 December. The resultant ash cloud rose ~2 km above the volcano and deposited ash on nearby towns. CENAPRED indicated that this type of activity is related to the destruction of the lava dome. According to a news article, a series of small eruptions just before Christmas deposited ash in towns as far away as central Texas. According to the article, "Upper-level winds just happened to be flowing from the Pacific Ocean over central México towards Texas, and that "jet stream" effectively transported the ash right into central Texas." There were reports of ashfall from San Antonio to New Braunfels, in addition to Austin, covering cars and vegetation with a light, white film. Sources: Centro Nacionale de Prevencion de Desastres, Associated Press, News 8 Austin -------------------------------------------------------------------------------- 31 December 2002- 7 January 2003 Based on information from the México City MWO, the Washington VAAC reported that a thin plume was visible on satellite imagery on 1 January at 1245. According to the MWO, the plume was at a height of ~7.3 km a.s.l. Sources: Centro Nacionale de Prevencion de Desastres, Associated Press, News 8 Austin -------------------------------------------------------------------------------- 15-21 January 2003 Volcanic activity continued at low-to-moderate levels at Popocatépetl during 15-20 January. Activity consisted of small-to-moderate emissions of steam, gas, and small amounts of ash, and sporadic episodes of low-amplitude harmonic tremor. On 9 January photographs of the lava dome revealed that the dome's inner crater had subsided. The lava dome's volume was calculated to be approximately 500,000 m3. Explosive activity after the 15th was probably associated with the growth of a new lava dome. CENAPRED stated that in the next days moderate explosive activity, with ash and incandescent material emission, could occur. Sources: Centro Nacionale de Prevencion de Desastres, Associated Press -------------------------------------------------------------------------------- 22-28 January 2003 Volcanic activity continued at low-to-moderate levels at Popocatépetl during 21-27 January. Activity consisted of small-to-moderate emissions of steam, gas, and small amounts of ash, and sporadic episodes of low-amplitude harmonic tremor. On 22 January at 0735 a significant increase in volcanic microsesimicity was recorded. According to the Washington VAAC, on the 25th an ash emission reached a height of ~10.7 km a.s.l. CENAPRED reported that the recorded seismic and volcanic activity were probably associated with the growth of a new lava dome inside the crater. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 29 January- 4 February 2003 Volcanic activity continued at low-to-moderate levels at Popocatépetl during 28 January to 3 February. Activity consisted of small-to-moderate emissions of steam, gas, and small amounts of ash, and sporadic episodes of low-amplitude harmonic tremor. A moderate-sized emission occurred on 2 February at 0826 that produced an ash column to a height of ~2 km above the volcano. In addition, there were episodes of harmonic low-amplitude tremor during 2 hours. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 5-11 February 2003 During 4-10 February, several moderate-sized emissions at Popocatépetl sent ash plumes to a height of ~2 km. On 4 February at 0459 a moderate dome-destruction explosion ejected incandescent volcanic material that fell as far as ~2 km down the volcano's flanks. On 5 and 6 February similar sized emissions occurred that were accompanied by episodes of low-amplitude harmonic tremor for up to 3 hours. According to CENAPRED, due to the remains of a lava dome inside the crater, there remained a significant chance of further explosive activity, ash emissions, and incandescent ejections around the crater. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 12-18 February 2003 A moderate explosion at Popocatépetl on 14 February at 0534 ejected incandescent fragments as far away as 3 km around the crater. Also, a dense ash column rose 5 km above the volcano and drifted NE. The ejected fragments caused some fires in pasture land. This eruption was related to the partial destruction of the lava dome. After the eruption, activity returned to low-to-moderate emissions of steam, gas, and ash. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 19-25 February 2003 Several emissions of steam, gas, and ash occurred during 19-25 February associated with the continued destruction of Popocatépetl's lava dome. One of the larger emissions occurred on 21 February at 1820 and produced a NE-drifting ash cloud to a height of 4 km above the volcano. It was followed by an emission the next day at 0239, which produced a NE-drifting ash cloud to 2 km above the volcano. Both emissions ejected incandescent fragments ~1.5 km from the volcano, causing fires in pasture land. According to the Washington VAAC, emissions on the 22nd produced two ash plumes that were visible on satellite imagery; one extended from the central Gulf of Mexico to the Yucatan Peninsula at a height ~10.7 km a.s.l., and a second smaller plume was over the Bay of Campeche at ~9.4 km a.s.l. Later that day, ash was visible on satellite imagery extending from Lake Okeechobee, Florida, NE into the Atlantic Ocean. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC, Associated Press -------------------------------------------------------------------------------- 26 February- 4 March 2003 Several emissions of steam, gas, and ash occurred during 26 February to 4 March associated with the continued destruction of Popocatépetl's lava dome, although there were fewer larger emissions than the previous week. The largest reported emission occurred on 28 February at 0314, with incandescent volcanic fragments ejected ~1 km around the crater and an ash emission that initially drifted E. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 5-11 March 2003 Several emissions of steam, gas, and ash occurred during 5-11 March associated with the continued destruction of Popocatépetl's lava dome. The largest reported emission, on 5 March at 1005, produced a steam-and-ash cloud that reached a height of 1 km above the crater. Also, a microearthquake and isolated episodes of low-amplitude harmonic tremor were recorded. The Alert Level at Popocatépetl remained at Yellow Phase II, with a 12-km-radius restricted area. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 12-18 March 2003 Several emissions of steam, gas, and ash occurred during 12-18 March associated with the continued destruction of Popocatépetl's lava dome. The largest reported emission, on 13 March at 0916, produced a steam-and-ash cloud that reached a height of 1 km above the crater and drifted E. According to a news article, ash fell on several communities near the volcano. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC, Associated Press -------------------------------------------------------------------------------- 19-25 March 2003 Several emissions of steam, gas, and ash occurred during 19-25 March associated with the continued destruction of Popocatépetl's lava dome. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 26 March-1 April 2003 Several emissions of steam, gas, and ash occurred during 26 March to 1 April associated with the continued destruction of Popocatépetl's lava dome. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 2-8 April 2003 During 2-8 April, moderate emissions of mainly gas and steam occurred at Popocatépetl. In addition, isolated episodes of low-amplitude harmonic tremor were occasionally recorded. There were still remains of the lava dome in Popocatépetl's crater. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 9-15 April 2003 During 9-15 April, moderate emissions of mainly gas and steam occurred at Popocatépetl. In addition, isolated episodes of low-amplitude harmonic tremor were occasionally recorded. There were still remains of the lava dome in Popocatépetl's crater. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 16-22 April 2003 The ongoing eruption at Popocatépetl was punctuated by a small explosion on 17 April, an event accompanied by incandescent fragments that reached 1 km E along the summit crater's outer margin, and a modest ash plume directed toward the NE. Associated with the event, low-amplitude tremor persisted for about 2 hours, but no other significant geophysical changes were seen. More typical low-intensity outbursts also continued during the week, typically at rates of ten's per day. The alert level still stood at Yellow, and the mountain road across the N flank remained open. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 23-29 April 2003 On 24 April at 2050 Popocatépetl issued a moderate explosion that threw incandescent fragments 1.5-2.0 km above the crater and generated an ash column that rose to ~2.5 km above the crater. The plume was initially carried E. This activity was related to the destruction of a small dome that formed in the past few days. After the explosion, activity dropped to its previous more tranquil levels. A small explosion occurred late on 26 April, followed by a clear increase in vigor on 28 April, including another moderate explosion at 0120 that day. Incandescent fragments landed on the E and NE flanks up to ~800 m from the crater. The outburst included a 40-second phase of greatest intensity. Ash falls were not reported. Hours later on 28 April instruments began to register harmonic tremor of moderate amplitude, signals that continued for 13 hours. During the next day the eruptive vigor dropped to modest levels (only four exhalations of low intensity occurred, a smaller number than typical, and chiefly containing steam and gas rather than ash). Scientists attributed the 28 April eruption and increased eruptive vigor to advanced rates of lava ascent and extrusion. They suggested that these may have been higher than seen either earlier this year or near the end of last year. The hazard status was raised one increment, to Yellow phase 3. In addition, the highway traversing the Cortés pass was closed to traffic for two days, 29-30 April. Source: Centro Nacionale de Prevencion de Desastres (CENAPRED) -------------------------------------------------------------------------------- 7-13 May 2003 During 7-10 May, moderate emissions of mainly gas and steam occurred at Popocatépetl. In addition, isolated episodes of low-amplitude harmonic tremor were occasionally recorded. No signs of a new lava dome were seen during a flight over the volcano on 20 April. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 11-17 June 2003 CENAPRED reported that a small eruption at Popocatépetl on 10 June at 1744 produced a W-drifting ash column to a height of ~3 km above the volcano. In addition, episodes of low-amplitude harmonic tremor were recorded for a total of 2 hours. According to the Washington VAAC, the volcano returned to just gas venting after the eruption. Based on information from the México City MWO, the Washington VAAC also reported that a small emission occurred on 15 June at 1401. Aviators reported that the cloud from this eruption rose to ~2 km above the volcano and drifted N. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 18-24 June 2003 During 18-24 June, moderate emissions of mainly gas and steam, and sometimes ash, occurred at Popocatépetl. In addition, isolated episodes of low-amplitude harmonic tremor were occasionally recorded. One of the more significant emissions, on 20 June at 0636, produced an ash-and-steam plume to a height of ~2 km above the volcano. Ash plumes were occasionally visible on satellite imagery. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 25 June-1 July 2003 During 25 June to 1 July, moderate emissions of mainly gas, steam, and sometimes ash, occurred at Popocatépetl. On 28 June the number of emissions was higher than on other days, and the plumes had a higher ash content. Ash fell in towns SW of the volcano. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 2-8 July 2003 During 2-8 July, moderate emissions of mainly gas, steam, and sometimes ash, occurred at Popocatépetl. A relatively large ash emission occurred on 2 July at 0755 that produced an ash cloud to ~3.5 km above the crater. After the event, volcanism returned to previous levels characterized by frequent and small emissions of steam and gas. Sources: Centro Nacionale de Prevencion de Desastres, Associated Press -------------------------------------------------------------------------------- 9-15 July 2003 During 9-15 July, moderate emissions of mainly gas, steam, and sometimes ash, occurred at Popocatépetl. An eruption on 9 July at 0910 sent ash to a height of ~1 km above the summit. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 16-22 July 2003 During 16-22 July, moderate emissions of mainly gas and steam occurred at Popocatépetl. On 19 July at 0920 a moderate explosion produced an ash plume that rose ~3 km above the crater. After the event the volcano returned to its previous level of activity characterized by frequent and small steam-and-ash emissions. According to news reports, a small amount of ash fell in Mexico City. The international airport remained open, with minor disruptions to air traffic. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 23-29 July 2003 During 23-29 July, moderate emissions of mainly gas, steam, and sometimes ash occurred at Popocatépetl. Aerial photography taken on 21 July revealed than an external lava dome was not visible at the bottom of the crater. A significant explosion occurred on 25 July at 2053, throwing incandescent fragments on Popocatépetl's slopes. According to news reports, the loud explosion panicked some residents in nearby communities. Sources: Centro Nacionale de Prevencion de Desastres, Associated Press -------------------------------------------------------------------------------- 30 July- 5 August 2003 During 30 July-5 August, moderate emissions of mainly gas, steam, and sometimes ash occurred at Popocatépetl. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 6-12 August 2003 During 6-12 August, moderate emissions of mainly gas, steam, and sometimes ash occurred at Popocatépetl. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 27 August- 2 September 2003 Aerial photography taken on 25 August revealed no external lava dome in Popocatépetl crater. On 28 August the number of low-level emissions increased in comparison to previous days. On 29 August at 1330 a low-density ash emission rose to ~1.5 km above the crater and drifted W. There were no reports of ash fall in villages near the volcano. This event was accompanied by episodes of high-frequency and low-amplitude tremor. By 1 September the number of emissions returned to levels recorded prior to the increase. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 17-23 September 2003 During 17-23 September, moderate emissions of mainly gas, steam, and sometimes ash occurred at Popocatépetl. According to the Washington VAAC, on 21 September a small possible ash cloud was visible on satellite imagery at a height of ~7 km a.s.l., extending NW from the summit. The cloud dissipated rapidly. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 5-11 November 2003 This tall volcano is commonly obscured by clouds and scientists are then forced to rely on seismicity detected by the monitoring network to define the number of "daily exhalations." Daily exhalations during the week of 5-11 November 2003 typically stood at ~5. By comparison, during March 1996 the daily exhalations reached ~180. Other monitored parameters during 5-11 November also indicated relative stability. Scientists also consider the energy released by the exhalation-related seismicity, and not surprisingly, this also stood much higher during mid-1996. A 17 October 2003 flight over the volcano allowed scientists to see into the crater; the crater floor looked comparatively flat, without signs of a rising dome. Good visibility on 6 November brought little sign of fumarolic steam rising from the volcano. No aviation ash advisories were issued for Popocatépetl during this week. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 19-25 November 2003 Activity at Popocatépetl remained stable during the week with numerous gas-and-steam emissions. Based on information from the Mexico City MWO, the Washington VAAC reported that an ash plume was emitted on 22 November that rose to ~9.5 km a.s.l. and extended ~19 km NE. Sources: Centro Nacionale de Prevencion de Desastres, Washington VAAC -------------------------------------------------------------------------------- 24-30 December 2003 During December relatively low-level volcanic activity continued at Popocatépetl, with low-intensity steam-and-gas emissions occurring. An aerial photograph taken on 10 December showed subsidence of the inner crater and no external lava dome at the bottom of the crater. The Alert Level remained at Yellow Phase II. Source: Centro Nacionale de Prevencion de Desastres -------------------------------------------------------------------------------- 24-30 March 2004 Popocatépetl remained at a low level of activity for the reporting period, occasionally producing gas-and-steam plumes. On 25 March the volcanic alert status was lowered to Yellow-1. Source: CENAPRED -------------------------------------------------------------------------------- 26 May- 1 June 2004 On 26 May at 0643 a small emission from Popocatépetl of steam, gas, and small amounts of ash produced a plume that reached a height of ~1.5 km above the volcano's crater. Ash fell in Tetela del Volcán, Morelos. Also, an M 2.4 volcano-tectonic microearthquake occurred 2 km E of the crater. Aerial photography taken on 14 April showed continued subsidence of the inner crater. No external lava dome at the bottom of the crater was distinguished. The Alert Level at Popocatépetl remained at Yellow Phase 1, therefore access was restricted in a 12-km-radius around the volcano. Source: CENAPRED, Agence France-Presse -------------------------------------------------------------------------------- 5-11 January 2005 On 9 January, the Washington VAAC reported that an ash plume rose up to ~10 km a.s.l. from Popocatépetl and extended S. Satellite imagery indicated that by 10 January, ash clouds had reached the coast of Mexico to the volcano’s S and SW. Source: CENAPRED, Agence France-Presse -------------------------------------------------------------------------------- 19-25 January 2005 According to the Washington VAAC, an explosion at Popocatépetl on 22 January produced a NE-drifting ash plume. CENAPRED reported that aerial photographs taken on 14 January showed subsidence in the inner crater of Popocatépetl and no external lava dome at the bottom of the crater. Popocatépetl remained at Alert Level Yellow- Phase 1, with access restricted within a 12-km radius around the crater. Source: CENAPRED, Washington Volcanic Ash Advisory Center -------------------------------------------------------------------------------- 2-8 February 2005 Based on information from the Mexico City MWO, the Washington VAAC reported that a small ash-bearing emission occurred on 3 February. No ash was visible on satellite imagery. Source: Washington Volcanic Ash Advisory Center -------------------------------------------------------------------------------- 2-8 March 2005 Based on information from the Mexico City MWO, the Washington VAAC reported that an ash emission from Popocatépetl around 0151 on 5 March rose to a height of ~7.3 km a.s.l. Source: Washington Volcanic Ash Advisory Center