Past decade ties for world's hottest: UN agency

Marlowe Hood AFP Yahoo News 29 Nov 11;

Thirteen of the warmest years recorded have occurred within the last decade and a half, proving that global warming is a reality, the UN's World Meteorological Organisation said on Tuesday.

The year 2011 caps a decade that ties the record as the hottest ever measured, the WMO said in a provisional report on climate trends and extreme weather events, unveiled at UN climate talks in Durban.

"Our science is solid and it proves unequivocally that the world is warming and that this warming is due to human activities," WMO Secretary-General Michel Jarraud said in a statement, adding that policy makers should take note of the findings.

"Concentrations of greenhouse gases in the atmosphere have reached new highs and are very rapidly approaching levels consistent with a 2 to 2.4 Celsius rise in average global temperatures."

Scientists believe that any rise above the 2.0 threshold could trigger far-reaching and irreversible changes over land and in the seas.

The 2002-2011 period equals 2001-2010 as the warmest decade since 1850, the report said.

2011 ranks as the 10th warmest year since 1850, when accurate measurements began.

This was true despite a cooling La Nina event -- one of the strongest in 60 years -- that developed in the tropical Pacific in the second half of 2010 and continued until May 2011.

The report noted that the cyclical climate phenomenon, which strikes every three to seven years, helped drive extreme weather events including drought in east Africa, islands in the equatorial Pacific and the southern United States.

While La Nina, and its meteorological cousin El Nino, are not caused by climate change, rising ocean temperatures caused by global warming may affect their intensity and frequency, scientists say.

Average surface temperatures over land were above long-term averages in most regions.

"There is no single country that has reported 2001-2010 mean temperatures that are colder than their national long-term average from 1961-1990," WMO Deputy Secretary General R.D.J. Lengoasa told journalists in Durban, citing a forthcoming review of weather trends over the last ten years.

For 95 percent of 80 countries that had submitted relevant data, 2001-2010 was the warmest decade on record, he added.

Forty percent had seen national heat records broken in 2001-2010, as compared to 15 percent in the 1991-2000 period, and 10 percent in the 1981-1990 period.

"Urgent action is needed to prevent the worst climate change scenarios in the coming decades," Lengoasa said.

Sea ice in the Arctic shrank to its second lowest surface area after 2007, and has reached record levels of thinness.

Extreme weather events in 2011 -- some influenced by La Nina -- hit regions unevenly.

In eastern Africa, where agriculture is almost entirely rain-fed, severe drought affected many countries, especially Kenya, Somalia and parts of Ethiopia.

Some 13 million people required emergency aid, according to the UN Office for Coordination of Humanitarian Affairs (OCHA).

In East Asia, rainfall during the 2011 monsoon season was far above average, with Thailand and Laos most affected. Floods claimed nearly 1,000 lives across Thailand, Cambodia and Myanmar.

Fourteen weather-climate events in the United States each caused at least one billion dollars in losses.

In central and south America, rainfall exceeding 200 millimetres (eight inches) in a few hours left at least 900 dead in the mountains north of Rio de Janeiro, one of the deadliest natural disasters in Brazil's history.

For the second year in a row, Pakistan saw severe flooding, though more localised -- in the south -- than in 2010.

A separate report also released Tuesday showed that Pakistan, Guatemala and Colombia were the countries worst hit in 2010 by extreme weather events.

Over a 20-year span, Bangladesh, Myanmar and Honduras were shown to be most vulnerable to Nature's violent outbursts, said the report, by European NGO Germanwatch.

WMO: 2011 One Of Hottest Years On Record
Jon Herskovitz PlanetArk 30 Nov 11;

The world is getting hotter, with 2011 one of the warmest years on record, and humans are to blame, a report by the World Meteorological Organization (WMO) said on Tuesday.

It warned increasing global average temperatures were expected to amplify floods, droughts and other extreme weather patterns.

"Our science is solid and it proves unequivocally that the world is warming and that this warming is due to human activities," WMO Deputy Secretary-General Jerry Lengoasa told reporters in Durban, where almost 200 nations are gathered for U.N. climate talks.

The WMO, part of the United Nations, said the warmest 13 years of average global temperatures have all occurred in the 15 years since 1997. That has contributed to extreme weather conditions that increase the intensity of droughts and heavy precipitation across the world, it said.

"Global temperatures in 2011 are currently the tenth highest on record and are higher than any previous year with a La Nina event, which has a relative cooling influence," it said

This year, the global climate was influenced heavily by the strong La Nina, a natural phenomenon usually linked to extreme weather in Asia-Pacific, South America and Africa, which developed in the tropical Pacific in the second half of 2010 and continued until May 2011.

One of the strongest such events in 60 years, it was closely associated with the drought in east Africa, islands in the central equatorial Pacific and the United States, as well as severe flooding in other parts of the world.

The WMO report was released to coincide with U.N. climate talks which run until December 9 in Durban aimed at trying to reach agreement on cutting planet-warming greenhouse gas emissions.

Prospects for a meaningful agreement appear bleak with the biggest emitters the United States and China unwilling to take on binding cuts until the other does first. Major players Japan, Canada and Russia are unwilling to extend commitments that expire next year and the European Union is looking at 2015 as a deadline for reaching a new global deal.

The WMO report said the extent of Arctic sea ice in 2011 was the second lowest on record, and its volume was the lowest.

It said the build-up of greenhouse gases put the world at a tipping point of irreversible changes in ecosystems.

"Concentrations of greenhouse gases in the atmosphere have reached new highs," WMO Secretary-General Michel Jarraud said in a separate statement.

"They are very rapidly approaching levels consistent with a 2-2.4 degree Centigrade rise in average global temperatures which scientists believe could trigger far reaching and irreversible changes in our Earth, biosphere and oceans."

Russia experienced the largest variation from average, with its northern parts seeing January to October temperatures about 4 degrees C higher in several places, it said.

U.N. scientists said in a separate report this month an increase in heat waves is almost certain, while heavier rainfall, more floods, stronger cyclones, landslides and more intense droughts are likely across the globe this century as the Earth's climate warms.

The Organization for Economic Cooperation and Development said global average temperatures could rise by 3-6 degrees Celsius by the end of the century if governments failed to contain emissions, bringing unprecedented destruction as glaciers melt, sea levels rise and small island states are submerged.

(Editing by Maria Golovnina and Janet Lawrence)

Human Role in Global Warming Unequivocal, Say World's Meteorologists
Environment News Service 29 Nov 11;

DURBAN, South Africa, November 29, 2011 (ENS) - Global temperatures in 2011 are currently the 10th highest on record and are higher than any previous year with a La Niña event, which has a cooling influence. The 13 warmest years have all occurred in the 15 years since 1997.

The extent of Arctic sea ice in 2011 was the second lowest on record, and its volume was the lowest.

These facts are drawn from the provisional annual World Meteorological Organization Statement on the Status of the Global Climate, which gives a global temperature assessment and a snapshot of weather and climate events around the world in 2011. It was released today at the United Nations climate conference in Durban, South Africa.

"Our role is to provide the scientific knowledge to inform action by decision makers," said WMO Secretary-General Michel Jarraud. "Our science is solid and it proves unequivocally that the world is warming and that this warming is due to human activities," he said.

"Concentrations of greenhouse gases in the atmosphere have reached new highs," warned Jarraud. "They are very rapidly approaching levels consistent with a 2 to 2.4 degree Centigrade rise in average global temperatures, which scientists believe could trigger far reaching and irreversible changes in our Earth, biosphere and oceans."

Global temperatures in 2011 have not been as warm as the record-setting values seen in 2010 but have likely been warmer than any previous strong La Niña year, based on preliminary data compiled by the World Meteorological Organization.

The global combined sea surface and land surface air temperature for January-October 2011 is estimated at 0.41°C plus or minus 0.111°C (0.74°F plus or minus 0.20°F) above the 1961-1990 annual average of 14 degrees Celsius (57.2 degrees Fahrenheit).

The 10-year average for the period 2002-11, at 0.46 degrees Celsius above the long-term average, equals 2001-10 as the warmest 10-year period on record.

Final annual figures for 2011 will be available once November and December data are available in early 2012.

Global climate in 2011 was heavily influenced by the strong La Niña event which developed in the tropical Pacific in the second half of 2010 and continued until May 2011.

This event, which on most measures was one of the strongest of at least the last 60 years, was closely associated with many of the year's notable regional climate events, including drought in east Africa, the central equatorial Pacific and the southern United States, and flooding in southern Africa, eastern Australia and southern Asia.

Strong La Niña years are typically 0.10 to 0.15 degrees Celsius cooler than the years preceding and following them. 2011's global temperatures followed this pattern, being lower than those of 2010, but were still warmer than the most recent moderate to strong La Niña years.

La Niña conditions have redeveloped in recent weeks but are not expected to approach the intensity seen in late 2010 and early 2011.

Surface air temperatures were above the long-term average in 2011 over most land areas of the world.

The largest departures from average were over Russia, especially in northern Russia where January-October temperatures were about 4°C above average in places. The spring was especially warm in this region with some stations more than 9°C above average for the season, while European Russia had another hot summer - the third-hottest on record in Moscow - although not as extreme as that of 2010.

The hot summer conditions extended into other northern countries, with Helsinki, Finland having its hottest summer in nearly 200 years of data, and Armenia setting an all-time national record (43.7°C).

Spain has had its hottest January-October period on record and several other western European countries approached records.

January-October 2011 was 1°C or more above average over large parts of Europe, southwest Asia and northern and central Africa, as well as the southern United States and northern Mexico, most of eastern Canada, and Greenland.

The Central American region is on course to have its hottest year in at least 140 years.

The most significant area of below-normal temperatures in 2011 was in northern and central Australia where temperatures were up to 1°C below average in places, largely the result of above-average cloudiness and heavy rain early in the year.

Other regions to experience below-normal temperatures in 2011 included the western United States and south-western Canada, and parts of east Asia including the Indochina Peninsula, eastern China and the Korean Peninsula.

Flooding affected many parts of the world in 2011, both flash floods and longer-lived events. In terms of loss of life, the most extreme single event occurred in Brazil on January 11-12, when a flash flood, caused by rainfall which exceeded 200 millimeters in a few hours, in mountainous terrain about 60 kilometers north of Rio de Janeiro caused at least 900 deaths. This was one of the worst natural disasters in Brazil's history.

It was a year of extremes in the United States, with 14 separate weather/climate events which caused losses of US$1 billion or more each.

Extreme drought affected parts of the southern United States and adjacent parts of northern Mexico. The core of the drought was in Texas, where state-wide averaged rainfall for January-October 2011 was 273 millimetres (56 percent below normal), well below the previous record of 327 millimeters set in 1956.

The drought region also had an exceptionally hot summer, with Texas's June through August mean temperatures (30.4°C (86.7°F), being 3.0°C (5.4°F) above the long-term average and the highest ever recorded for any American state. In addition to agricultural losses and water shortages, impacts of the drought included severe wildfires and dust storms.

Many northern and central parts of the United States experienced heavy rain and flooding in 2011. The January-October period was the wettest on record for several northeastern states and for the northeast region as a whole, with precipitation totals widely 30-50 percent above normal.

The most severe floods in this region, reaching record levels in places, were associated with Hurricane Irene in August and Tropical Storm Lee in September.

Spring and early summer were extremely wet in many central areas, particularly the Ohio Valley and the upper Midwest of the United States and the Prairie provinces of Canada, which experienced some of the worst flooding on record. There was also substantial spring flooding in the north-eastern United States and the Canadian province of Quebec. The heavy spring rains, combined with the melting of a heavy winter snowpack in northern areas, caused major downstream flooding during May and June. Parts of the Mississippi River experienced the worst floods since 1933, and there was also major flooding in the Missouri River and several Canadian rivers.

It was also one of the most active tornado seasons on record, with numerous major outbreaks, particularly in April and May. A tornado caused 157 deaths in Joplin, Missouri in May, the deadliest single tornado in the United States since 1947. To date, 2011 has had the third-greatest number of tornadoes since 1950, after 2004 and 2008, and 537 deaths, the fourth-greatest number of deaths on record. There were also a number of major snowstorms, including the most significant October snowstorm on record in the northeastern states.

This preliminary information for 2011 is based on climate data from networks of land-based weather and climate stations, ships and buoys, as well as satellites. The data are continuously collected and disseminated by the National Meteorological and Hydrological Services of the 189 governments that are Members of WMO and several collaborating research institutions. The content of the WMO statement is verified and peer-reviewed by experts from other international, regional and national climate institutions and centers before its publication.