Storms and Floods

Tropical Storms – Roundup of Tropical Storms:

Gl sst mm

In the North Atlantic Ocean: Subtropical Depression One is located about 730 mi…1170 km WSW of the Azores with maximum sustained winds…35 mph…55 km/h. Present movement…N or 350 degrees at 14 mph…22 km/h.

NewsBytes:

Uganda – Heavy rains that have pounded some parts of the eastern region since mid-March on Monday washed away three bridges on the Mbale-Tirinyi road, leaving one person dead. Hundreds of stranded motorists had to find alternative routes after unseasonable rainfall hit the villages for nearly three hours.

Colombia – Flooding and mudslides in central Colombia have killed at least 11 people, the Red Cross said Wednesday, causing alarm in a country still recovering from recent mudslides that killed hundreds. At least 20 people are missing after torrential rains lashed the city of Manizales, officials said, raising fears the death toll could soar as it did earlier this month in the southern city of Mocoa.

F03733d3 b7cd 4f61 a7bd 0e631cd0cb90

Global Warming

Antarctic meltwater lakes threaten sea levels – study

Antarctic meltwater lakes are far more common than once thought and could destabilise glaciers, potentially lifting sea levels by metres as global warming sets in, scientists said on Wednesday.

Most vulnerable are the massive, floating ice shelves that ring the Antarctic continent and help prevent inland glaciers from sliding toward the sea, they reported in the journal Nature.

Antarctica holds enough frozen water to push up global oceans by tens of metres.

Meltwater pooling on the surface of ice shelves can suddenly drain below the surface, fracturing the ice with heat and pressure, studies have shown.

Rising temperatures are eroding ice shelves – which can be hundreds of metres thick and extend hundreds of kilometres over ocean water – on two fronts, scientists say.

From above, warmer air and shifting winds remove snow cover, exposing the bedrock ice underneath. Because ice has a darker, blueish tint, it absorbs more of the Sun’s radiation rather than reflecting it back into space.

But the main damage to ice shelves comes from ocean water eroding their underbellies.

Normally, that erosion is compensated by the accumulation of fresh snow and ice from above.

But oceans in recent decades have absorbed much of the excess heat generated by global warming, which has lifted average global air temperatures by 1°C since the mid-19th century.

Temperatures in Earth’s polar regions have risen twice as fast during the same period. On the Antarctic Peninsula – which juts north toward South America – they have shot up by 3.5°C in just the last 50 years.

Disease

Italy – Measles Outbreak Update

In a follow-up on the measles outbreak in Italy, health officials have reported 1603 measles cases since the beginning of the year through Apr. 16, according to the Ministero della Salute today.

Nigeria – Meningitis Outbreak Update

The meningococcal meningitis numbers keep piling up in parts of Nigeria as officials now put the case count at 8,057 suspected cases and 745 deaths as of Monday, according to the Nigeria Centre for Disease Control (NCDC).

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 12 April – 18 April 2017

Aira | Kyushu (Japan) : JMA reported that a very small eruption at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) occurred on 16 April. The Alert Level remained at 3 (on a 5-level scale).

Ibu | Halmahera (Indonesia) : Based on ground and satellite observations, PVMBG and the Darwin VAAC reported that during 12-13 and 17 April ash plumes from Ibu rose 1.5-1.8 km (4,900-5,900 ft) a.s.l. and drifted S and SW.

Kambalny | Southern Kamchatka (Russia) : KVERT reported that observers in the South Kamchatka Sanctuary noted an ash plume from Kambalny rising to an altitude of 7 km (23,000 ft) a.s.l. on 9 April. Ash plumes identified in satellite images drifted 50 km NE on 9 April and about 170 km SE the next day. The Aviation colour Code remained at Orange.

Manam | Papua New Guinea : RVO reported that incandescence from both Manam’s Southern Crater and Main Crater fluctuated in intensity during 1-15 April, and incandescent material was occasionally ejected from the craters. RSAM values averaged around 100. On 15 April RSAM values fluctuated, with a peak of 450 at 0600 and other peaks throughout the day, though with RSAM values not as high. RVO interpreted the high RSAM values as changes in seismicity from discrete low-frequency earthquakes, to sub-continuous volcanic tremor, and then to continuous volcanic tremor.

During 0300-0800 on 16 April RSAM values were high (peaking at 400); there were no reports of associated anomalous eruptive activity, though RVO noted communication problems. Based on RSAM data, a small-to-medium eruption began between 1400 and 1600 on 16 April. Seismicity was initially erratic, and peaked at about 0030 and 0100 on 17 April. A Dugulava village resident (S side of island) briefly viewed the eruption and reported that incandescent material was ejected from the crater and fell into the N and SW valleys. Rumbling and roaring was also heard. Activity decreased around 0600 and remained low until the next day. Strong Strombolian activity at Southern Crater was observed at about 1300 on 18 April, and roaring and rumbling was heard. Dense and dark ash clouds rose a few hundred meters above the crater rim and drifted NW. Two small pyroclastic flows descended the SE and SW valleys, terminating at about 1 km a.s.l. At about 1500 Strombolian activity subsided, coinciding with a very loud explosion. Activity fluctuated though was low until 2100, and then afterwards light-gray ash plumes rose above the crater. White-to-gray ash plumes rose above Main Crater during 17-18 April, and small ejections of material occurred about every five minutes.

Poas | Costa Rica : OVSICORI-UNA reported that a strong 40-minute phreatic eruption from an area in between the lava dome and the hot lake at Poás was recorded on 12 April starting at 1830. An eruption column consisting of water, altered rocks, sediments, and gases was produced; the height of the column could not be determined due to poor visibility. Ash fell around the crater and to the NW in Bajos del Toro. A water-level increase of 2 m in the Desague River, with headwaters at the S part of the crater, was noted. According to news articles the National Emergency Committee (CNE) evacuated residents living near the Desague River. The Poás Volcano National Park closed the next day.

At 1546 on 13 April an eight-minute-long eruption produced a plume that rose 500 m above the crater rim. The event rendered a webcam on the N rim inoperable. Events at 0758 (strong) and 1055 on 14 April generated plumes of an unknown height. A 10-minute-long event which began at 0810 on 15 April again produced a plume of unknown height. Frequent (2-3 events per hour) small short-lived phreatic eruptions were recorded by seismographs during 15-16 April. A plume that rose 500 m followed an eruption at 0946 on 16 April. Later that day, at 1350, an event generated a plume that rose 1 km. A news article reported that boulders as large as 2 m in diameter fell in an area 30 m away from a tourist trail, breaking a water pipe. Rocks also damaged fences and concrete floors in viewing areas. Small, frequent, and short-lived phreatic eruptions continued to be recorded through 18 April. A video posted by a news outlet showed an explosion ejecting incandescent material.