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Record average temperatures highlight the urgent need to agree a deal on emissions at the UN climate change talks in Lima.
Vehicles drive by a 134ft-high thermometer in Baker, California. Average land and sea surface temperatures have reached record levels in 2014. Photograph: Ethan Miller/Getty Images.
Suzanne Goldenberg, The Guardian.
The world is on course for the hottest year ever in 2014, the United Nations weather agency said on Wednesday, heightening the sense of urgency around climate change negotiations underway in Lima.
Preliminary estimates from the World Meteorological Organisation (WMO) found global average land and sea surface temperatures for the first 10 months of 2014 had soared higher than ever recorded.
The findings – broadly in line with those of the US National Oceanic and Atmospheric Administration (Noaa) and other scientific agencies – indicate that by year-end 2014 will break all previous high temperature records.
The steady escalation of greenhouse gas emissions, caused by the burning of fossil fuels, have seen a succession of record-breaking years for temperature since the dawning of the 21st century and 2014 promises to be no exception, the WMO said.
“Fourteen of the 15 warmest years on record have all occurred in the 21st century,” said the WMO’s secretary-general Michel Jarraud. “What we saw in 2014 is consistent with what we expect from a changing climate.
“Record-breaking heat combined with torrential rainfall and floods destroyed livelihoods and ruined lives. What is particularly unusual and alarming this year are the high temperatures of vast areas of the ocean surface, including in the northern hemisphere,” he said.
The new evidence provided by the WMO report of the gathering risks of climate change undercut the optimism expressed by negotiators from industrialised countries at the opening of the Lima talks.
Christiana Figueres, the UN’s top climate official, said the findings drove home the urgency of reaching a deal. Negotiations have been grinding on for more than 20 years.
“Our climate is changing and every year the risks of extreme weather events and impacts on humanity rise,” she said.
Ed Davey, the UK climate secretary, said the UN climate talks were critical to stop temperatures rising to dangerous levels. “More record warm temperatures in the UK and across the world are yet more evidence that we need to act urgently to prevent dangerous climate change,” he said.
Officials from nearly 200 countries will spend the next two weeks in Lima working to agree on a plan to cut global greenhouse gas emissions fast enough and deeply enough to limit warming to 2C above pre-industrial times, the official objective of the UN talks.
But even that goal – which scientists say may not go far enough to prevent low-lying island states from drowning in rising seas – may be moving beyond reach.
“When confronted with numbers like these, the challenge to stablise global warming below dangerous levels can seem daunting indeed,” Michael Mann, the climate scientist, said. “The globe is warming, ice is melting, and our climate is changing, as a result. And the damage is being felt – in the forms of more destructive weather extremes, more devastating wildfires, and unprecedented threats to the survival of endangered animal species.”
He said the Lima climate talks – and a summit scheduled for Paris at the end of next year – were “perhaps our last real opportunity to stave off truly dangerous and irreversible world-wide changes in our climate.”
Bill McKibben, leader of the 350.org campaign group, saw the findings as a call to arms to climate activists. “If you thought 2014 was hot, wait ‘til you see 2015. This means we need to turn up the flame even higher under the fossil fuel companies that are frying our planet,” he said.
Londoners enjoying record temperatures at Halloween. Photograph: Rob Stothard / Getty Images.
The WMO report found the global average air temperature over land and sea surface for January to October was about 0.57C above the average of 14C for the 1961-1990 reference period, and 0.09C above the average for the past 10 years (2004-2013).
The most striking evidence of warming was probably in the oceans, however. Most of the excess heat trapped in the atmosphere by greenhouse gas emissions ends up in the oceans.
The WMO said global sea surface temperatures were 0.45C higher than the average over the last 50 years.
If November and December continue on the same course, then 2014 will edge out 2010, 2005 and 1998 as the hottest years ever known – but only by a few hundredths of a degree. Different data sets also show slightly different rankings, the WMO said.
In any event, the trend line is clear. The world is getting warmer, especially the oceans. Those higher temperatures were already exacting a toll, in terms of heavy rainfall and flooding in some countries, and extreme drought in others, the WMO said.
The agency dismissed outright the notion posed by some climate deniers of a pause in the warming trend.
“There is no standstill in global warming,” Jarraud said.
But scientists say even those targets are not enough to limit warming to 2C, and other big carbon polluters such as India, Russia, and Australia have yet to come on board.
Meanwhile, there were early signs of tension between the US and EU over the legal structure of the agreement that is due to be adopted in Paris next year.
Campaign groups monitoring the talks called on negotiators to take the new WMO findings to heart.
“The fact that we’re tracking towards the hottest year on record should send chills through anyone who says they care about climate change – especially negotiators at the UN climate talks here in Lima,” said Samantha Smith, who heads WWF’s climate and energy initiative. “This is more scientific evidence of the real impact climate change is having on our world. The changes will be felt the most by the most vulnerable people, whose lives and livelihoods are already being affected.”
An almost dried up reservoir in Pingdingshan, central China’s Henan province, where severe drought damaged vast areas of farmland. Photograph: STR / AFP / Getty Images.
The WMO found western North America, Europe, eastern Eurasia, much of Africa, large areas of South America and southern and western Australia were especially warm. South Africa, Australia, and Argentina started the year with blistering heat waves.
However, the US and Canada ushered in 2014 with the chill Arctic winds of the polar vortex. Central Russia also recorded cooler than average conditions for the year.
Europe also experienced extreme weather, with the UK buffeted by storms. A separate temperature data set, the world’s longest continuous record, showed England was on track for the hottest year in over three centuries. Higher temperatures cause more evaporation and more rain, and 2014 began with England’s wettest winter in over 250 years, leading to widespread flooding.
In Serbia, Bosnia-Herzegovina and Croatia, more than two million people were caught up in severe flooding. Parts of Turkey saw five times the normal amount of rain, and France experienced its wettest summer since 1959.
South Asia also experienced heavy rains, with severe flooding in northern Bangladesh, northern Pakistan and India, affecting millions of people in August and September.
For other parts of the world, however, 2014 brought drought. Rainfall in parts of the Yellow River basin in China were less than half of the summer average. A large swathe of the western US continued under drought. New South Wales and southeast Queensland in Australia also went without rain.
By Megan Darby
The scientists took measurements from icebreaker ship Oden. (Pic: Stockholm University/Stella Papadopoulou)
When researchers from Stockholm University found plumes of methane rising from the seabed, the chief scientist’s response was mild.
“This was somewhat of a surprise,” Örjan Gustafsson wrote in his blog .
When glaciologist and blogger Jason Box saw their findings, he put it rather more strongly: “That’s damn scary.”
The subject of Box’s concern was methane released from the ocean. Methane is a potent greenhouse gas, with around 20 times the warming effect of carbon dioxide.
What is more, the scientists suspect climate change could make such methane releases more likely, in a feedback loop.
Box, who has been studying the Greenland ice sheet’s sensitivity to weather and climate for 20 years, was already losing sleep about occasional spikes in methane levels in the area. He called these outlying results “dragon’s breath”.
While there was growing evidence of high methane levels over the Arctic Ocean, this Swedish study was the first to record methane bubbles rising to the surface.
Gustafsson and his team were exploring the Laptev Sea, on the edge of the Arctic.
From icebreaker ship Oden, they used sonar and chemical analysis to measure methane in the water.
They found plumes of the gas rising from depths of between 150m and 500m. Levels of dissolved methane in the water were between 10 and 50 times background levels.
Gustafsson said the gas may be released from methane hydrates collapsing on the sea bed.
“While there has been much speculation about the vulnerability of regular marine hydrates along the continental slopes of the Arctic rim, very few actual observations of methane releases due to collapsing marine hydrates on the Arctic slope have been made,” he blogged.
A “tongue” of warmer water from the Atlantic could be behind the breakdown of methane hydrates. There is some evidence that part of the ocean is getting warmer.
Box said the findings showed the importance of reducing man-made carbon emissions.
“Fossil fuel burning is the trigger mechanism poking the climate dragon,” he wrote. “The cautionary principle makes clear we have to keep this dragon in the ground.”
Rise in blocking-patterns – hot or wet weather remaining stuck over regions for weeks – causing frequent heatwaves or floods.
By Damian Carrington.
A man hangs on to a trash can as rain water gushes towards Albuquerque in New Mexico, US. Heavy rains caused flash flooding and road closures in the city earlier this month. Photograph: Roberto E. Rosales/AP
The work shows so-called “blocking patterns”, where hot or wet weather remains stuck over a region for weeks causing heatwaves or floods, have more than doubled in summers over the last decade. The new study may also demonstrate a link between the UK’s recent flood-drenched winter and climate change.
Climate scientists in Germany noticed that since 2000 there have been an “exceptional number of summer weather extremes, some causing massive damage to society”. So they examined the huge meanders in the high-level jet stream winds that dominate the weather at mid-latitudes, by analysing 35 years of wind data amassed from satellites, ships, weather stations and meteorological balloons. They found that blocking patterns, which occur when these meanders slow down, have happened far more frequently.
“Since 2000, we have seen a cluster of these events. When these high-altitude waves become quasi-stationary, then we see more extreme weather at the surface,” said Dr Dim Coumou, at the Potsdam Institute for Climate Impact Research. “It is especially noticeable for heat extremes.” The intense heatwaves in Russia in 2010, which saw 50,000 people die and the wheat harvest hit hard, and in western Europe in 2003, which saw 30,000 deaths, were both the result of blocking patterns. The Intergovernmental Panel on Climate Change concluded in 2011 that extreme weather would become more common as global warming heats the planet, causing both heatwaves and increasingly severe rain storms.
In 2010, heatwaves caused hundreds of wildfires across Russia. Above, a man tries to stop a fire near Dolginino village. Photograph: Artyom Korotayev/AFP/Getty Images.
The rise in blocking patterns correlates closely with the extra heating being delivered to the Arctic by climate change, according to the research which is published in the journal Proceedings of the National Academies of Science (PNAS). Coumou and his colleagues argue there are good physical reasons to think there is a causal link, because the jet streams are driven by the difference in temperature between the poles and the equator. As the Arctic is warming more quickly than lower latitudes, that temperature difference is declining, providing less energy for the jet stream and its meanders, which are called Rossby waves.
Prof Ted Shepherd, a climate scientist at the University of Reading, UK, but not involved in the work, said the link between blocking patterns and extreme weather was very well established. He added that the increasing frequency shown in the new work indicated climate change could bring rapid and dramatic changes to weather, on top of a gradual heating of the planet. “Circulation changes can have much more non-linear effects. They may do nothing for a while, then there might be some kind of regime change.”
Shepherd said linking the rise in blocking events to Arctic warming remained “a bit speculative” at this stage, in particular because the difference between temperatures at the poles and equator is most pronounced in winter, not summer. But he noted that the succession of storms that caused England’s wettest winter in 250 years was a “very good example” of blocking patterns causing extreme weather during the coldest season. “The jet stream was stuck in one position for a long period, so a whole series of storms passed over England,” he said.
Flooding in Northmoor Green (Moorland) in Somerset, UK, in February this year. Photograph: David Levene for The Guardian.
Coumou acknowledges his study shows a correlation – not causation – between more frequent summer blocking patterns and Arctic warming. “To show causality, computer modelling studies are needed, but it is questionable how well current climate models can capture these effects,” he said.
Prof Tim Palmer, at the University of Oxford, wrote in a PNAS article in 2013 that understanding changes to blocking patterns may well be the key to understanding changes in extreme weather, and therefore to understanding the worst impacts of climate change on society. But he said climate models might have to run down to scales of 1km to do so. “Currently, national climate institutes do not have the high-performance computing capability to simulate climate with 20km resolution, let alone 1km,” he wrote. “I look forward to the day when governments make the same investment in climate prediction as they have made in finding the Higgs boson.”
Firefighters cross a flooded intersection on Route 110 in Farmingdale, N.Y., on New York’s Long Island, Wednesday, Aug. 13, 2014. Stranded Long Island drivers have been rescued after a storm slammed Islip, N.Y., with over 13 inches of rain — an entire summer’s worth. (AP Photo/Frank Eltman)
DEER PARK, N.Y. (AP) — A storm has slammed a suburban New York area with over 13 inches of rain — an entire summer’s worth — and trapped drivers on flooded roads around Long Island.
The staggering total was recorded Wednesday at an airport in the hamlet of Ronkonkoma (rahn-KAHN’-kuh-muh) in the town of Islip (EYE’-slip). Joe Pollina of the National Weather Service says the area’s normal total for June, July and August is 11.75 inches.
The Southern State Parkway was closed around Baldwin and about 20 miles east in Deer Park, where cars were stuck in a couple of feet of water.
WPIX says fire crews in boats rescued drivers in Nesconset (nehs-KAHN’-seht).
Central and eastern Long Island roads that were still open had bumper-to-bumper traffic Wednesday.
The rain started around 6 p.m. Tuesday. It tapered off Wednesday morning.
Vehicles are submerged on a flooded section of the Northern State Parkway, near Route 107, in Jericho, N.Y., on New York’s Long Island, Wednesday Aug. 13, 2014. Stranded Long Island drivers have been rescued after a storm slammed Islip, N.Y., with over 12 inches of rain — an entire summer’s worth. (AP Photo/Newsday, Howard Schnapp) NYC LOCALS OUT
Human-caused global warming is causing the upper troposphere to become wetter.
by Water vapor emanating from steaming cooling towers of a Slovakian nuclear power plant. Photograph: Joe Klamar/AFP/Getty Images
We have long suspected that greenhouse gases which cause the Earth to warm would lead to a wetter atmosphere. The latest research published by Eul-Seok Chung, Brian Soden, and colleagues provides new insight into what was thought to be an old problem. In doing so, they experimentally verified what climate models have been predicting. The models got it right… again.
To be clear, this paper does not prove that water vapor is a greenhouse gas. We have known that for years. Nevertheless, the paper make a very nice contribution. The authors show that the long-term increase in water vapor in the upper troposphere cannot have resulted from natural causes – it is clearly human caused. This conclusion is stated in the abstract,
Our analysis demonstrates that the upper-tropospheric moistening observed over the period 1979–2005 cannot be explained by natural causes and results principally from an anthropogenic warming of the climate. By attributing the observed increase directly to human activities, this study verifies the presence of the largest known feedback mechanism for amplifying anthropogenic climate change.
As stated earlier, climate models have predicted this moistening – before observations were available. In fact, the models predicted that the upper troposphere would moisten more than the lower atmospheric layers. As the authors state,
Given the importance of upper-tropospheric water vapor, a direct verification of its feedback is critical to establishing the credibility of model projections of anthropogenic climate change.
To complete the experiments, the authors used satellite measurements of radiant heat. The emissions have changed but it wasn’t clear why they have changed. Changes could be caused by increases in temperature or from increased water vapor. To separate the potential effects, the authors compared the first set of experiments with others made at a different wavelength. That comparison provided a direct measure of the separate effect of moistening.
Next, the authors used the world’s best climate models to test whether the observed trends could be caused by natural changes in the Earth’s climate or whether they require a human influence. Sure enough, only the calculations that included human-emitted greenhouse gases matched the observations. The authors conclude that,
Concerning the satellite-derived moistening trend in recent decades, the relations of trend and associated range among three experiments lead to the conclusion that an increase in anthropogenic greenhouse gases is the main cause of increased moistening in the upper troposphere.
The authors then went further by showing that their computed results encompass third-party measurements only when the impacts of human-emitted greenhouse gases are included.
I chuckled when I asked Dr. Andrew Dessler about this study, and he told me,
Because of water vapor’s importance as a greenhouse gas, the water vapor feedback occupies a central role in the climate system. Over the years, our understanding of this process has increased steadily, and this paper is a very useful contribution. It nicely demonstrates that the observations of upper tropospheric moistening are unlikely to have arisen without the increase in carbon dioxide from human activities. At this point, I think it would be fair to say, “stick a fork in it, the water vapor feedback’s done.”
So once again, observations have confirmed the models and the scientists can check another item off their “to do” box.