Earth ChangesS


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New Clues to Prehistoric Extinction

trilobite
© Wikipedia / CBSA trilobite found in the Burgess Shale region of the Canadian Rockies
Scientists Say Cambrian Extinction Resulted from Too Much Sulfur, Too Little Oxygen

About 540 million years ago, things were looking pretty rosy for complex life on Earth. Conditions were favorable, and the diversity of multicellular organisms took off during the so-called Cambrian Explosion. Trilobites frolicked. Brachiopods abounded. And then, things went south.

Between 490 million and 520 million years ago, a swift extinction event wiped out many of the Cambrian lifeforms. Geologists Benjamin Gill and Graham Shields-Zhou thinks they have found the trigger right in the midst of that era. According to their study in this week's Nature, the ocean's oxygen level plunged and the sulfur levels rose sharply 499 million years ago, killing off species that could not quickly adapt. That included some, but not all, of the trilobites that ruled the seas of the time.

According to Science News, Gill's team decided to look at a specific subset of Cambrian extinctions that began 499 million years ago and lasted for 2 million to 4 million years. Other researchers had proposed that low oxygen levels - a condition known as anoxia - could be involved. But no one had marshaled enough evidence to prove that.

Blackbox

UK: Beach closed after discovery of strange substance

A beach has been closed after the discovery of a mysterious substance.

An "unidentified foam-like substance" has been found along part of the southern coastline, causing Chichester District Council to close East Wittering beach until further notice.

Beaches controlled by West Wittering Estate and Cakeham Manor have also been closed.

A council spokesperson said: "We are closing the beach as a precaution. The unidentified foam-like substance was discovered earlier today. The Environment Agency has taken samples to test. We should know the outcome of these tests within the next 48 hours.

"Following this time, we will decide on what action to take."

Cloud Precipitation

Non-Stop Rains Damage 2,929 Hectares of Rice Fields in Albay

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© AllVocies
Manila, Philippines - Some 2,929 hectares of rice farmlands were damaged by the continuous rains in Albay, the Department of Agriculture said in a report on Tuesday.

The damaged rice areas are 12 municipalities in the province of Albay that have been flooded due to the heavy rains that have been battering the region, according to Marilyn V. Sta Calataina, the DA Bicol regional technical director who has placed production loss at about P13.37 million.

Majority of the affected rice crops were either newly planted or in their vegetative stage as the cropping season has just started, Catalina said.

Of the 2,929 affected areas, 85.8 percent or 2,516 hectares were considered to "have a chance of recovery" and only 413 hectares were destroyed, with no chance of recovery.

The areas greatly affected by the flooding are: Tabaco City with over 932 hectares; Legaspi City with over 592 hectares and Malinao with over 420 hectares.

Cloud Lightning

Flash Floods Alert - Tasmania

flipped care
© Ross MarsdenA car flipped on the Midland Hwy at Perth in slippery conditions.
The weather bureau yesterday renewed warnings about heavy rain and flash flooding in the north and northeast today and tomorrow.

Bureau of Meteorology Media and Community Relations manager Malcolm Riley said computer models were suggesting that several hundred millimetres of rain could fall between Tuesday midnight and Friday midnight.

"Heavy falls are expected about the north and northeast where there is the possibility of flash flooding ," Mr Riley said.

"Northern rivers could reach at least moderate flood level.

The warnings come as police warned motorists to drive with caution in the extreme weather.

A car flipped on its roof in slippery conditions on the Midland Hwy near Perth yesterday and the driver was lucky to escape without serious injuries.

Cloud Lightning

US: Heavy Rains, Strong Winds Could Hit Kauai and Oahu Wednesday

Honolulu -- The National Weather Service placed Kauai and Oahu under a flash flood warning Wednesday morning as an anticipated storm system arrived.

The storm is also forecast to bring strong southwest winds. A wind advisory for much of the state begins at noon Wednesday.

Kauai and Oahu could see the worst of the storm on Wednesday, forecasters said.

Forecasters said conditions could bring heavy showers or thunderstorms and stall over the central islands on Thursday.

Forecasters say the heaviest rainfall amounts will most likely affect the western half of the state, but that there could be a threat of flash flooding on all islands. There is also a chance of thunderstorms that may cause rainfall totals to increase even more.

Monitor the latest forecasts and stay with KITV.com and KITV4 News.

Cloud Lightning

Heavy Sri Lankan Floods Kill Over A Dozen

flood,sri lankan
© UnknownFloods have inundated the Sri Lankan capital of Colombo
Sri Lankan government officials have confirmed that flooding caused by heavy rains has taken 18 lives and forced 200,000 people to evacuate their homes.

Monsoon rains in the east and north-eastern parts have caused flooding which has affected an estimated one million people according to the State Disaster Management Centre.

Flood waters are reported to be up to one metre in some areas and warnings of mudslides have been issued. The flooding comes as Australia and the Philippines battle devastating floods of their own. Europe is also just recovering from a severe winter snap that caused massive public and transportation delays.

The Sri Lankan government has sent in its army, navy and air force to help in the relief effort. It is estimated that around 160,000 of rice paddy fields have been flooded causing worries about the years rice harvest.

Cloud Precipitation

Australian Floods Damage Crops; More Rains Forecast

australia,floods
© AP Photo/NASAIn this image provided by NASA taken on Jan. 7, 2010, the Advanced Spaceborne Thermal Emission and Reflection Radiometer instrument on NASA's Terra spacecraft captured this image of the inundated city of Rockhampton, Queensland, Australia. For Australia, La Ni?a typically means above-average rains, and the current La Ni?a is no exception. Heavy rains that began in late December led to the continent's worst flooding in nearly a half century, at its peak inundating an area the size of Germany and France combined. Rockhampton is the largest city affected by the current flooding. Torrential rains in northeastern Australia caused the Fitzroy River to overflow its banks and flood much of the city and surrounding agricultural lands. Both the airport and major highways are underwater, isolating the city. In this natural color rendition, muddy water is brown, and shallow, clearer water is gray. Vegetation is depicted in various shades of green, and buildings and streets are white.
Heavy rainfall and flooding that prompted widespread production downgrades and caused considerable damage to crops in Australia's eastern states look set to continue, with the government's Bureau of Meteorology Tuesday posting severe weather warnings for many areas.

Rabobank Australia downgraded its production forecast for Australian cotton, sugar and sorghum crops in 2011, and said there are further downside risks, potentially reducing availability for exports.

Premier Anna Bligh declared the entire northeast state of Queensland a disaster zone after massive rains and flash floods to the west of Brisbane city killed nine people Monday. Bligh said the death toll could double, with scores still missing.

Red Flag

The Tragic State of the Gulf of Mexico: Sampling Reveals Oil and Dispersants on Mississippi Coast

deadfish
© Erika Blumenfeld
In October 2010, Truthout tested several water and soil samples from the Gulf of Mexico for chemicals in BP's crude oil and toxic dispersants. One sample of dead marine life was also tested.

Truthout also obtained and had analyzed a sample of pure Corexit 9500, one of the toxic dispersants used to sink the crude oil. The dispersants BP has used in the Gulf of Mexico are banned in at least 19 other countries. BP has used at least 1.9 million gallons of the dispersants in the Gulf of Mexico to sink their 4.9 million barrels of crude oil.

The samples were tested in a private lab via gas chromatography by an analyst who requested anonymity.

Lab tests have confirmed oil and chemicals from the dispersants in the samples tested, which contradicts ongoing statements from both BP and the Obama administration that the Gulf of Mexico is safe from the effects of the BP oil disaster.

Corexit 9500

dead fish
© Erika Blumenfeld
These two vials were filled with saltwater and a small amount of motor oil. Two drops of Corexit 9500 were added to the vial on the left and both vials were gently shaken for 30 seconds. Both samples then sat for one hour before this picture was taken.

The milky color of the water in the vial on the left displays the manner in which the dispersant causes a portion of the oil to dissolve into the water. When crude oil in the Gulf is treated with dispersant, a large portion of the oil is also dissolved into the seawater, allowing harmful volatile contaminants to also dissolve into the water, which would have otherwise evaporated had the oil been sitting on the surface.

This theory is nothing new, but this picture displays this phenomenon visually. After nine days, there was still no sign of any separation between the dissolved oil and water at all. In fact, it currently appears that the effect has only increased over time.

Cloud Lightning

Zimbabwe: Water supply critical despite heavy rains

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Bulawayo - Despite the current heavy rains pounding the city, the water supply situation remains critical with the four dams currently having a combined total water supply of 40, 69 % compared to 52 % during the same period last year.

In an interview with The Zimbabwean, the mayor, Thaba Moyo, said despite the current rains, the city's dams had received insignificant inflows resulting in major water supply challenges for the city.

"As the year starts, the water supply situation remains critical with current water supply at a total of 40.69 %. Council is monitoring the inflows in this current rainy season and will continue to keep a close eye on the rate of consumption in order to ensure that the situation is kept under control," said the mayor.

He added that the city's water situation has also been worsened by the increasing population.

Cloud Precipitation

Australia Floods Inundate Brisbane, Over 90 Missing

Thousands of residents of Australia's third-largest city evacuated homes on Wednesday as massive floods threatened to inundate the financial district, sparked panic buying of food and left authorities despairing for more than 90 people missing.

The biggest floods in decades have so far killed 14 people since starting their devastating march across the northern mining state of Queensland last month, crippling the coking coal industry, destroying infrastructure, sending the local currency to four-week lows and threatening to put a brake on the economy.

With a flood surge expected to peak in the Queensland capital of Brisbane, a city of two million, on Thursday, search and rescue crews took advantage of rare sunshine on Wednesday to look for those still missing from tsunami-like flash floods that tore through townships west of the city this week.

"I think we're all going to be shocked by what they find in these towns that were hit by that tsunami yesterday," Queensland state Premier Anna Bligh told local television on Wednesday.

The worsening floods are forcing economists to raise estimates of the economic impact, with one central bank board member quoted on Wednesday as saying the disaster could cost as much as 1 percent of economic growth -- equal to almost $13 billion, double the previous highest estimate.