Earthquakes

Magnitude 5+ Earthquakes – Global

5.2 earthquake hits the Nicobar Islands off India.

5.0 earthquake hits the Pacific-Antarctic ridge.

Storms and Floods

Tropical Storms – Roundup of Tropical Storms:

There are no current tropical storms.

NewsBytes:

Malaysia – The death toll in Malaysia floods has risen to at least 37. Triggered by days of heavy rain, the floods have also displaced nearly 70,000 people. Meanwhile, in Pahang state, several towns remain cut off.

Environment

Deforestation Heat

Workers in the tropics have increasingly been exposed over the past 15 years to heat that makes their outdoor labours unhealthful and even hazardous. Scientists say this is due to a combination of deforestation and climate change.

But Luke Parsons of Duke University found that the most challenging conditions for outdoor workers are occurring in areas where forests have been felled. “The trees in the tropics seem to limit the maximum temperatures that the air can reach. Once we cut those trees down, we lose that cooling service from the trees, and it can get really, really hot,” Parsons says. He adds that the increased heat and humidity in deforested areas increase the risk of heat-related illnesses, including deadly heat stroke.

Wildlife

Arctic Beavers

Beavers are slowly migrating farther north into the Arctic due to the warming climate, producing what a new U.S. government report says is a “significant impact” on the landscape.

NOAA’s Arctic Report Card 2021 says western Alaska has seen a doubling of its beaver population to more than 12,000 during the past 20 years, compared to none between 1949 and 1955. Their dams are increasing surface water and adding to the rate of permafrost melt, which in turn releases the greenhouse gases methane and carbon dioxide. The ponds are also said to be helping new fish and invertebrate species move in.

Environment

Global Temperature Extremes

The week’s hottest temperature was 45.5 degrees Celsius (114 degrees F) at Jervois, South Australia.

The week’s coldest temperature was minus 55.0 degrees Celsius (-67 degrees F) at Oimyakon, Siberia.

Temperatures were tabulated from the more than 10,000 worldwide synoptic weather stations. The United Nations World Meteorological Organization sets the standards for weather observations, and provides a global telecommunications circuit for data distribution.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 15 December – 21 December 2021

Aira – Kyushu (Japan) : JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were detected during 13-20 December. The sulfur dioxide emission rate was slightly high at 1,200 tons per day on 13 December. Crater incandescence was visible at night during 13-17 December.

Fuego – Guatemala : INSIVUMEH reported that 3-13 explosions per hour were recorded at Fuego during 14-21 December, generating ash plumes as high as 1.1 km above the crater rim and periodic shock waves that were felt in communities around the volcano. Ash plumes drifted as far as 40 km NW, W, SW, and SE; ashfall was reported in areas downwind, including Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), San Pedro Yepocapa (8 km NW), Sangre de Cristo (8 km WSW), finca Palo Verde, Santa Sofía (12 km SW), and Yucales (12 km SW) during 16-18 and 20-21 December. Block avalanches descended the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), and Las Lajas (SE) drainages, often reaching vegetated areas. Explosions ejected incandescent material up to 100-300 m above the summit during 14-15 and 17-19 December. Winds lifted “curtains” of ash around the volcano during 18-19 December, and crater incandescence was visible overnight during 20-21 December.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin likely continued during 15-19 December and very low seismicity persisted. A radar image acquired during 14-15 December showed a growing flow field with lava lobes advancing down the N, W, and S flanks. Elevated surface temperatures at the summit were detected overnight during 15-16 and 18-19 December.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was visible in satellite images during 11, 13, and 15-16 December.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava effusion continued at a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 14-20 December. The sulfur dioxide emission rate was about 1,400 tonnes per day on 16 December. By 19 December the lake had risen a total of 69 m since the beginning of the eruption. A series of partial overturns of the lake was visible on 20 December, though by the next morning there was no lava effusion from the vent and the lake had crusted over.

La Palma – Spain : Observations at La Palma on 15 December showed no lava flowing from vents at the W base of the main cone, from tubes, or at the lava delta in the Las Hoyas area. During 15-20 December tremor levels were at background levels and seismicity was very low at all depths. Sporadic gas emissions rose from the vents and from cooling lava flows. Small collapses from the walls of the main and secondary cone craters were visible through the week. Sulfur dioxide levels varied between extremely low and medium values (less than 5 to 999 tons per day) consistent with a cooling and degassing lava flow field. Even though air quality levels had improved overall, a few measurements of diffuse carbon dioxide emissions showed levels around 9 times average background. Authorities warned the public to exercise caution in areas surrounding the flow field due to volcanic gases in the area and noted that lava flows, although cooling, remained at high temperatures.

Lewotolok – Lembata Island (Indonesia) : PVMBG reported that the eruption at Lewotolok continued during 14-21 December. White, gray, and black ash plumes that were sometimes dense rose as high as 1 km above the summit. Incandescent material was ejected from the vent up to 300 m often to the E and SE, but sometimes in all directions. Rumbling and booming sounds were often heard.

Manam – Papua New Guinea : The Darwin VAAC reported that a thermal anomaly over Manam was identified in satellite images on 15 December, prior to an ash emission that rose to 6.1 km (20,000 ft) a.s.l. and drifted SW. An ash plume rising to the same altitude was visible in satellite images on 16 December but had dissipated by mid-morning. Later that day diffuse ash plumes rising to 2.4 km (8,000 ft) a.s.l. were visible in satellite images and reported by ground observers, according to RVO. An eruptive event was recorded by the seismic network at 0600 on 17 December; ground observations indicated that an ash plume likely rose to 3 km (10,000 ft) a.s.l. and drifted SE. At 0840 ash emissions identified in satellite images and by observers rose to 3 km, drifted SE, and dissipated within about five hours. At 0220 on 18 December an ash plume rose to 3 km, drifted SE, and again dissipated within about five hours; a thermal anomaly over the summit was visible in the satellite data. At 1600 on 21 December an ash plume rose to 1.5 km (5,000 ft) a.s.l., drifted NE, and dissipated within about three hours. The thermal anomaly persisted.

Merapi – Central Java (Indonesia) : BPPTKG reported no significant morphological changes at Merapi’s lava domes, located just below the SW rim and in the summit crater, during 10-16 December. The estimated dome volumes were almost 1.63 million cubic meters for the SW dome and just over 3 million cubic meters for the summit dome. The intensity of the seismic signals remained at high levels. As many as 116 lava avalanches traveled a maximum of 2 km SW down the Bebeng drainage, and three pyroclastic flows traveled a maximum of 2.2 km SW. At 1643 on 18 December a pyroclastic flow advanced 2 km SW and produced an ash plume that rose 400 m.

Pavlof – United States : AVO reported seismicity at Pavlof was elevated during 14-21 December and was mainly characterized by periods of sustained tremor and discrete low-frequency events. Strongly elevated surface temperatures were visible in satellite images during 14-16 and 18-21 December, consistent with lava effusion. Numerous small explosions were recorded during 19-21 December.

Popocatepetl – Mexico : CENAPRED reported that each day during 14-21 December there were 11-23 steam-and-gas emissions from Popocatépetl that drifted NW, NE, E, and SE.

Santa Maria – Guatemala : INSIVUMEH reported that in recent months the dome in Caliente crater, the active part of Santa María’s Santiaguito lava-dome complex, has grown due to a higher rate of extrusion. Blocky lava descending the W flank of the dome produced block avalanches, though avalanches often descended the flanks in multiple directions. A larger number of volcano-tectonic earthquakes began to be recorded on 11 December simultaneously with increased surficial activity. The lava extrusion rate increased on 16 December at the WSW part of the dome, causing intense incandescence at the dome, an increase in block avalanches on the W, S, and E flanks, and higher gas emissions. On 17 December strong explosions produced ash plumes that rose as high has 2 km above the dome and drifted 30 km W. Strong explosions continued to be recorded though 19 December; explosions were weak during 20-21 December. Ash fell in areas downwind including San Marcos Palajunoj (8 km SW) and Loma Linda (6 km WSW) during 16-18 December. Strong incandescence and block avalanches on the W, SW, and S flanks continued through 21 December.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that low-level eruptive activity and elevated seismicity at Semisopochnoi’s North Cerberus crater continued during 15-21 December. Small daily explosions were detected in seismic and infrasound data. Low-level ash-and-steam emissions were observed daily by webcams and were occasionally identified in satellite images when weather conditions permitted. Elevated surface temperatures were also identified in satellite data during 15-17 and 19-20 December.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 10-17 December.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that crater incandescence at Suwanosejima’s Ontake Crater was visible nightly during 13-20 December. The number of explosions increased on 15 December; there were 152 explosions during 13-17 December. Eruption plumes rose as high as 1.2 km above the crater rim and bombs were ejected 800 m from the vent. There were 288 explosions recorded during 17-20 December. Resulting plumes rose as high as 1.9 km above the crater rim and bombs were ejected as far as 800 m from the vent.

Yasur – Vanuatu : The Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur increased at around 2100 on 18 December. Thirty minutes later webcam images showed deposits of incandescent volcanic bombs that had been ejected from the crater and landed on the flanks. Ash-and-gas plumes were visible at 1015, 1430, and 1545 on 19 December drifting W.