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Arctic permafrost thawing faster than ever

Permafrost in the Arctic is thawing faster than ever, according to a new US government report that also found  Arctic   seawater is war...


martedì 17 maggio 2016


This year the Earth experienced the warmest April on record, keeping 2016 on track to be the hottest year yet and by the biggest margin ever.
New data released by NASA put this April's land and sea temperatures at 1.11 degrees Celsius warmer than average April temperatures between 1951 to 1980, which NASA uses as a reference point to study recent climate change.
It was the seventh month in a row to rise by at least 1 degree Celsius above the 1951-80 reference averages.
The data that just keeps getting worse has prompted scientists to declare a "climate emergency" and is already casting doubts on pledges made in the Paris agreement to keep temperature rises well below the 2 degrees Celsius that scientists say will have catastrophic consequences on the planet.
The agreement was hammered out in December but signed in record-breaking April, with the ambitious aim to cap temperature rises at 1.5 degress Celsius compared with pre-industrial levels.
Leaders also began a 10-day meeting in Bonn, Germany on Monday to follow up on the agreement and to work out just how to make these targets achievable.
Scientists and leaders have agreed that global greenhouse gas emissions will need to peak soon and be followed by quick reductions over the years ahead to contain temperature rises.
"In the second half of the century those emissions need to be so low they can be easily absorbed by the Earth's natural systems such as forests and soils," the U.N. Framework Convention on Climate Change said in a statement.
Temperature rises have had a boost in the past year from a strong El Nino, a weather event characterized by the warming of ocean waters in the tropical Pacific Ocean that brings extreme weather, including drought and heavy rains, to other parts of the world.
There is hope that a La Nina may be creeping in, which typically cools the Pacific waters.

Beyond two degrees

So what happens if the planet breaches the two degrees of warming threshold?
Nothing good, according to reports reviewed by CNN's John Sutter, who has written extensively on the subject.
Sutter -- who pulled reports from the National Research Council, the Intergovernmental Panel on Climate Change and the World Bank -- says wildfires in the United States could significantly increase in size, hurricanes would be slightly more intense, more species would be at risk for extinctionArctic ice would continue to melt, crop yields would decrease and the availability of freshwater would significantly decline.

2016 to be hottest year yet as April smashes records ay 16, 2016

Clima: il 2016 sarà l’anno più caldo di sempre. Ecco i dati della Nasa 17 maggio 2016

Australian emissions are on the increase, particularly in the electricity sector. Photo: Michele Mossop

Carbon dioxide continues to increase in the atmosphere with a major milestone of 400 parts per million of CO2 recorded in the Southern Hemisphere according CSIRO's Dr David Etheridge.

A significant marker of rising global greenhouse gas emissions has been passed, with a key monitoring site on Tasmania's north-west tip recording atmospheric carbon-dioxide exceeding 400 parts per million for the first time.

As foreshadowed by Fairfax Media last week, a baseline reading at the Cape Grim station that exceeded the 400-ppm mark of the primary gas driving global warming was imminent.

As it turned out, "the unfortunate milestone" was reached on Tuesday May 10 at 8am, local time, said Paul Krummel, who heads the CSIRO team analysing data from the most important site in the southern hemisphere.

Atmospheric readings from Cape Grim, along with two stations in Hawaii and Alaska, are closely watched as they date back decades and closely track a range of pollutants from ozone-depleting chemicals to the various greenhouse gases resulting from burning fossil fuels and clearing forests.

Mr Krummel said that while mostly symbolic, the 400-ppm reading "highlights the problem of rising emissions, which are increasing more rapidly than they used to be".

A report out earlier this year from the World Meteorological Organization noted atmospheric readings of CO2 at the Mauna Loa site in Hawaii rose 3.05 ppm in 2015 alone – the biggest increase in the 56 years of research.

The recent surge in CO2 levels was not unexpected because of the giant El Nino event now breaking up in the Pacific. In El Nino years, global temperatures get a kick higher and droughts tend to be worse. As a result, vegetation take out less CO2 from the atmosphere.

CSIRO's Mr Krummel said the El Nino influence was evident in Cape Grim's reading with barely a dip in the past year as might otherwise be expected in spring.

"This year, it's just plateaued and now it's taken off again," he said, adding the site was "probably one of the last places on earth" to remain below 400 ppm.

Sites in the northern hemisphere exceeded 400 ppm from 2012 onwards. But as the region has greater seasonal variation – mostly because there is more terrestrial vegetation – CO2 concentrations dropped back below that mark each spring.

Once Cape Grim gets past a short period with CO2 levels gyrating around 400 ppm, it will need a huge global effort to curb greenhouse gas emissions to push the level back down.

"It's not going to go back below 400 ppm for a very long time unless we get very good at mitigation," Mr Krummel said. Global CO2 levels were running at roughly 280 ppm up until about 1850 when they started to take off.

Climate scientists, such as David Karoly at Melbourne University, note that when other greenhouse gases, such as methane, are included, the situation is even bleaker.

The so-called carbon dioxide-equivalent level that takes in the full global warming impact is now about 485 ppm.

Both 2014 and 2015 were record hot years globally in data going back about 130 years. With the effect of a strong El Nino overlaying long-term trends, this year is likely to be even hotter after a scorching start.

Ed Hawkins, a climate scientist at the UK's University of Reading, has constructed the following animation showing how the world has warmed in the past 166 years.

Many regions of the world are experiencing unusual warmth for May, with parts of Alaska expected to be 15 degrees warmer than average.

Even Sydney is running about 5 degrees above average so far for May and Australia on the whole is headed for close to its warmest autumn on record.

The Cape Grim site, meanwhile, celebrated its 40th anniversary in March with a cloud over its future because of the CSIRO job cuts.

While management has promised to maintain the facility that it runs in cooperation with the Bureau of Meteorology, the number of CSIRO staff analysing the gases collected at the site is expected to be cut by about one-third from the current tally of about 30 researchers.

Confirmed: Southern hemisphere CO2 level rises above symbolic 400 ppm milestone Peter Hannam May 16, 2016

Canadian Climate Change Inferno 8 MAGGIO 2016

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