Record low in Arctic sea ice caused by global warming, says UN

[Magda Hassan]

Record low in Arctic sea ice caused by global warming, says UN

Global warming not only increased temperatures last year but caused a record low in Arctic sea ice, as well as deadly storms and economic uncertainty, the UN has warned.

By Louise Gray, Environment Correspondent
1:49PM BST 02 May 2013


The World Meteorological Organisation, that tracks the weather on behalf of the 193 countries of the United Nations, confirmed 2012 was the 9th warmest year on record.

The annual summary of climate change also warned Arctic sea ice reached its lowest ever level, rainfall increased causing floods around the world and a number of countries experienced drought.

Extreme weather events, like Superstorm Sandy in the US and Typhoon Bopha in the Philippines, were linked to climate change.

Michel Jarraud, Secretary-General of the WMO, said natural variability - like the La Nina/ El Nino pattern in the Pacific - means global warming will not necessarily make each year successively warmer than the last.

[URL="http://www.telegraph.co.uk/earth/environment/climatechange/10033034/Record-low-in-Arctic-sea-ice-caused-by-global-warming-says-UN.html"]Link to documents here
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However overall trends show temperatures continue to increase while extreme weather events also appear to be more common.
"Despite the cooling influence of à La Niña episode early in the year, 2012 joined the 10 previous years as one of the warmest at ninth place on record," he said. "Although the rate of warming varies from year to year due to natural variability caused by the El Niño/La Niña cycle, volcanic eruptions and other phenomena, the sustained warming of the lower atmosphere is a worrisome sign.
"The continued upward trend in atmospheric concentrations of greenhouse gases and the consequent increase in radiative forcing of the Earth's atmosphere confirm that the warming will continue."
[SUP]JanuaryDecember global land and ocean surface temperature anomalies (relative to 19611990) for the period 19502012[/SUP]
Here is a summary of the report:
Temperature in top ten hottest years
Global average temperature in 2012 was 0.45 degrees Celsius warmer than the 1961 to 1990 long term average of 14C, according to the report.
This is a relatively small increase compared to previous years and it can be said that global warming is "slowing down".
However in the wider context it is still following a warming trend.
Last year was the 27th consecutive year with an above average global temperature and the ninth warmest year on record. The years between 2001 and 2012 were among the top 13 warmest on record.
Arctic sea ice at lowest level ever
Arctic sea ice reached a record low of 3.41 million square kilometres in summer 2012.
Antarctic
In contrast to the northern polar region, sea ice in the south pole is growing in extent. Antarctic sea-ice extent last March was the fourth largest on record.
There are a number of theories for this, including some that claim climate change could be causing sea ice to increase in the south pole.
Extreme weather patterns
The WMO believes that extreme weather events, like storms, are being made worse by climate change.
Last year Hurricane Sandy killed more than 200 people and caused billions of dollars worth of damage. Typhoon Bopha killed even more people in Philippines.
M. Jarraud commented: "Because global sea levels are now about 20cm higher than they were in 1880 storms such as Hurricane Sandy are bringing more coastal flooding than they would have otherwise."
Floods and drought
Globally, rainfall was slightly higher in 2012 than the long term average for 1961 to 1990.
Northern Europe, western Africa, north-central Argentina, western Alaska, and most of northern China saw wetter than average conditions. Severe flooding occurred in Pakistan for a third consecutive year.
But much of the central United States, northern Mexico, northeastern Brazil, central Russia, and south-central Australia experienced drier-than-average weather
After experiencing dry conditions during the first three months, the remainder of the year in the UK was wet, resulting in the second wettest year on record, behind 2000.
Mr Jarraud pointed out climate change has become "a source of uncertainty for planners and decision-makers in climate-sensitive economic sectors".
He said meteorologists must work harder to find out what is causing global warming to slow down and predict what will happen in future.
"We need to better understand how much of the extra heat captured by greenhouse gases is being stored in the oceans and the consequences this brings in terms of ocean acidification and other impacts. We need to know more about the temporary cooling effects of pollution and other aerosols emitted into the atmosphere. We also need a better understanding of the changing behaviour of extreme weather and climate events as a consequence of global warming, and we need to assist countries in the most affected areas to better manage climate-related risks with improved climate early warning and climate watch systems." he added.
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