Magnitude 5+ Earthquakes – Global
5.7 earthquake hits the Krmedec Islands.
5.5 earthquake hits Bio-Bio, Chile.
5.5 earthquake hits the Kermedec Islands.
5.4 earthquake hits off the east coast of North Island, New Zealand.
5.2 earthquake hits off the coast of Oregon, USA.
5.1 earthquake hits Guerrero, Mexico.
5.0 earthquake hits Tonga.
Two 5.0 earthquakes hit off the coast of Oregon, USA.
5.0 earthquake hits the Kermedec Islands.
5.0 earthquake hits the Pagan region, North Mariana Islands.
5.0 earthquake hits southern Peru.
Tropical Storms – Roundup of Tropical Storms:
There are no current tropical storms.
Philippines – Hundreds of people have moved from their homes to evacuations centres after flash flooding in parts of Davao City. Heavy rains caused by a localized thunderstorm on 26 April triggered flooding in Bunawan and Buhangin-B districts. As many as 3,280 people were affected by the flooding incident in four and 162 families or 419 people evacuated to temporary shelter in 5 evacuation centres. Over 265 mm of rain fell at Davao Airport in 24 hours to 27 April 2021.
Massive DDT Dumping Ground off California Coast
The sea bottom near southern California has been hiding a very dirty secret: decades of discarded chemicals in thousands of barrels. And the toxic debris field is even bigger than anyone expected, containing at least 27,000 drums of DDT and industrial waste, scientists recently discovered.
High concentrations of DDT (dichlorodiphenyltrichloroethane, an insecticide that was widely used for pest control during the 1940s and 1950s) were previously detected in ocean sediments between the Los Angeles coast and Catalina Island, in 2011 and 2013. At the time, scientists who searched the seafloor in the area identified 60 barrels (possibly containing DDT or other waste) and found DDT contamination in sediments, but the full extent of the area’s contamination was unknown.
Now, a research expedition presents a clearer picture of the deep-sea dump site. Their findings reveal a stretch of ocean bottom studded with at least 27,000 industrial waste barrels — and possibly as many as 100,000.
Glaciers are Shrinking
Earth’s glaciers are shrinking, and in the past 20 years, the rate of shrinkage has steadily sped up, according to a new study of nearly every glacier on the planet.
Glaciers mostly lose mass through ice melt, but they also shrink due to other processes, such as sublimation, where water evaporates directly from the ice, and calving, where large chunks of ice break off the edge of a glacier, according to the National Oceanic and Atmospheric Administration (NOAA). By tracking how quickly glaciers are shrinking, scientists can better predict how quickly sea levels may rise, particularly as climate change drives up average global temperatures.
The team found that, between 2000 and 2019, glaciers collectively lost an average of 293.7 billion tons (267 billion metric tonnes) of mass per year, give or take 17.6 billion tons (16 billion metric tonnes); this accounts for about 21% of the observed sea-level rise in that time frame.
Wildfires – Siberia
Russian emergency services have reported an abnormally high number of fires in the Omsk oblast of southwest Siberia. On April 22, 2021, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this image of fires in the region. As of April 28, smoke from the fires was still visible.
The countries with the 10 greatest number of Covid-19 cases:
Roundup of Global Volcanic Activity – New Activity for the Week 21 April 2021 – 27 April 2021
Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Karymsky was visible in satellite images 16-17 and 22 April. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Piton de la Fournaise – Reunion Island (France) : OVPF reported that the eruption at Piton de la Fournaise continued during 21-27 April, though inclement weather conditions obscured visual observations most of the week. The average lava-flow rate was between 1.2 and 8.3 cubic meters per second during 16-23 April. The flow rates were estimated based on the gas-emission rates, though weather conditions may have affected the accuracy of the measurements. Lava continued to mostly flow in lava tubes; some flows thickened and parts of the flow field widened. The longest flow was 3.2 km long and the maximum width was 750 m, unchanged from the previous week. The flow field was mapped using a satellite image acquired on 24 April. The Alert Level remained at 2-2.
Semisopochnoi – Aleutian Islands (USA) : Eruptive activity at Semisopochnoi gradually increased during 21-22 April based on satellite and infrasound data; ash emissions were first seen in satellite images at 1800 on 21 April and were continuous at least through 1348 on 22 April. Plumes rose to 2.4 km (8,000 ft) a.s.l. and drifted 80 km S. Sulfur dioxide emissions were also detected in satellite images on 22 April. Cloud cover mostly obscured views during 23-24 April, though possible minor ash emissions were sometimes visible. Low-level ash plumes drifting S were occasionally identified in satellite images during 24-26 April. Dense weather clouds prevented views for most of 26 April and the next day. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.
Soufriere St. Vincent – St. Vincent : University of the West Indies Seismic Research Centre (UWI-SRC) reported that eruptive activity at Soufrière St. Vincent (often simply referred to as “La Soufriere”) was relatively low during 21-27 April with the exception of one explosive period. During 20-21 April seismicity was characterized by a few rockfalls and volcano-tectonic (VT) earthquakes, and an increasing number of small long-period (LP) and hybrid earthquakes. Sulfur dioxide emissions were again measured from a boat near the W coast, revealing a flux of 350 tons per day. At around 1108 on 22 April explosions produced an ash plume that rose as high as 8 km (26,200 ft) a.s.l. and drifted mainly N over the sea. High-level seismic tremor began at 1109 and lasted for about 20 minutes. Pyroclastic flows were generated early in the eruption and traveled down the W flank, reaching the sea within five minutes. Lahar signals were recorded later that day at about 2100. According to National Emergency Management Organisation (NEMO) the total number of displaced people was 13,154 by 21 April, with 6,208 people in 85 public shelters and 6,790 people (1,618 families) in private shelters. There were no casualties caused by the eruption. In a 22 April press release the Argyle International Airport announced that the ash cleanup was ongoing and that the Cargo Terminal was scheduled to open the next day. Seismicity dropped to low levels after the explosive event and remained at low levels through 27 April; only a few LP, hybrid and VT earthquakes were recorded. On 23 April the sulfur dioxide flux was 992 tons per day, recorded again from the W coast. A diffuse steam plume rose from the crater on 24 April. Satellite data most recently from 24 April, and seismic data suggested likely cycles of crater dome growth and destruction. During an overflight on 26 April scientists observed white steam plumes rising from several locations on the crater floor, though visibility was poor. No lava dome was visible, but a possible spine-like protrusion was seen through the clouds. Seismic signals indicating lahars were again recorded. Lahars in the Red and Orange zones were recorded by the seismic network at 0900 and 1000 on 27 April, during and after rainfall. The volcano Alert Level remained at Red.
Veniaminof – United States : AVO reported that eruptive activity at Veniaminof had declined during the previous few weeks; no emissions were visible after ash emissions on 5 April and seismicity continued to decline. On 21 April the Volcano Alert Level was lowered to Advisory and the Aviation colour Code was lowered to Yellow.