Global warming slowdown likely to be brief: U.S., UK science bodies

OSLO Thu Feb 27, 2014 4:27pm EST

A stream of water trickles on the bottom of the Almaden Reservoir near San Jose, California January 21, 2014. REUTERS/Robert Galbraith

A stream of water trickles on the bottom of the Almaden Reservoir near San Jose, California January 21, 2014.

Credit: Reuters/Robert Galbraith

Related Topics

OSLO (Reuters) - A slowdown in the pace of global warming so far this century is likely to be only a pause in a longer-term trend of rising temperatures, the science academies of the United States and Britain said on Thursday.

Since an exceptionally warm 1998, there has been "a short-term slowdown in the warming of Earth's surface," Britain's Royal Society and the U.S. National Academy of Sciences said in a report.

But, they said, that "does not invalidate our understanding of long-term changes in global temperature arising from human-induced changes in greenhouse gases."

The warming slowdown has emboldened those who question the evidence about climate change and ask whether a shift in investments towards renewable energies such as wind and solar power, advocated by many experts, is really needed.

But the report said that scientists were "very confident" that the planet would warm further this century, causing more extreme heatwaves, droughts and rising seas.

A build-up of greenhouse gases from human activities, mainly the burning of fossil fuels, is warming the atmosphere and the oceans, raising sea levels and melting Arctic ice, the report said, supporting the long-held view of a U.N. panel of climate scientists.

It projected that temperatures would rise by between 2.6 and 4.8 Celsius (4.7-8.6 F) by 2100 unless governments took strong action to limit rising emissions of greenhouse gases, broadly in line with U.N. estimates.

Temperatures have gained about 0.8 C (1.4 F) since the 19th century.

STAIRCASE

Almost 200 nations have agreed to work out a deal by the end of 2015 to combat climate change. So far there has been little progress in negotiations, partly because weak economic growth has sapped government interest.

Policy decisions were only possible if "based on the best possible advice about the science of climate change," Paul Nurse, President of the Royal Society, told a briefing.

The warming hiatus may be caused by shifts in the oceans that are absorbing more heat from the atmosphere, the report said. Other studies suggest that sun-dimming volcanic eruptions or a lower output from the sun may contribute.

Brian Hoskins, of Imperial College London, said warming trends in past decades had varied a lot despite rising greenhouse gas emissions. "It's a staircase rather than a gentle trend upwards," he said.

Among signs of rising temperatures, the report said that record heatwaves had hit Australia in 2013, the United States in 2012, Russia in 2010 and Europe in 2003. There had been fewer cold snaps, like in the United States this winter.

"It is now more certain than ever, based on many lines of evidence, that humans are changing Earth's climate," it said.

Last year, the U.N.'s panel on climate science raised the probability that human activities, rather than natural variations, were the main cause of warming since the 1950s, to at least 95 percent from 90 in a previous assessment in 2007.

(Editing by Robin Pomeroy)

FILED UNDER:
We welcome comments that advance the story through relevant opinion, anecdotes, links and data. If you see a comment that you believe is irrelevant or inappropriate, you can flag it to our editors by using the report abuse links. Views expressed in the comments do not represent those of Reuters. For more information on our comment policy, see http://blogs.reuters.com/fulldisclosure/2010/09/27/toward-a-more-thoughtful-conversation-on-stories/
Comments (10)
morbas wrote:
Local weather extremes, from drought to flood in the corn belt, simply to much over cast (wet) weather in the East for crops to grow, and California extreme drought (and wild fire). These from a supposedly ‘beneficial global +1 degree C warming’. SOL’s (our named sun) magnetic field weakens as it reverses, and Earth’s magnetic field also flipping (weakening); that both increase cosmic ray cloud cooling effect. But, alas too little or no avale (neutralizing) ‘beneficial +1 degree C’ industrial global warming. I urge the mislead people to read ‘Rare Earth’. NASA is finding thousands of planetary star system(s), and SETI does not detect a single ‘industrial’ extra terrestrial civilization; it is eerily quiet out there amongst this plethora of planetary systems.
–Greenland ICE volume 9 Meters Ocean Level Rise
–Antarctic ICE volume 73Meters Ocean Level Rise
We know what America looked like 100M years ago with no polar ice; two mountain ranges, Appalachian and Laramidia separated by the Western Interior Seaway. Florida completely awash. Russia and China would dominate the world.
We must forget our pettish differences, we may be fighting for survival of Democracy, to include USA, in one single planetary cause.

Engineering can address environmental issues, it will take a 10 year push. Here is what is needed…
Congress must push infrastructure projects to enable USA economics. Reduce/eliminate naval shipping that uses waste grade oil fuel without environmental controls. Switch to North/Central/South America Rail infrastructure to include a Trans-Bearing Strait route as a matter of efficiency. Re-Engineer rail gauge for reliability and speed. Make Truck/rail/freeway portals at interstate intersections, thus reducing fuel consumption and promoting local electric transport. Build national level canals for water distribution relieving drought by using excessive fresh water run of. We might then improve CO2 sequester by irrigating our mid plane deserts. One of the canal paths through the Rockies could be coupled with a SF to Denver Maglev 2G space ramp using a common power generation infrastructure. Thus promoting Maglev transit as a spinoff of Space Access Maglev launch capacity.
We should build on a strategic infrastructure designed to make USA a Global transportation hub, linking Americas (North Central South) to the old world. Not because this is easy or hard, because this will be our challenge, we must be willing to better mankind.
Thus we become a Space Faring Nation,
morbas(i)

Feb 27, 2014 6:16pm EST  --  Report as abuse
TrueScience wrote:
A paper published in Nature, published in late 2013, and online Jan 2, which says new data shows there has been no “pause” in global warming and that a 4C global temperature rise is now projected that would likely be “catastrophic” rather than simply “dangerous.” For example, it would make life difficult, if not impossible, in much of the tropics. And by about 2040, we’d be similarly affected. By 2100, global temperatures are projected to increase by 4C, life-threatening for most species, including humans. This assumes we continue with our current rates of use of fossil fuels.

The “pause” has been addressed in numerous other media, including January articles in both Scientific American and the Washington Post which explain that the “pause” was achieved by deniers manipulating the data by using a particular date to begin with, a 17 year period which was a freakishly cold El NiƱo year. Choose any other year and the “pause” disappears, replaced by a higher rate of warming than the long-term trend line.

Feb 27, 2014 7:56pm EST  --  Report as abuse
Miner49er wrote:
The dubious hypothesis of anthropogenic climate change will have been definitively falsified within five years. When ambient carbon dioxide declines or remains steady, even while CO2 emissions continue to rise, the only possible conclusion will be that CO2 does not cause climate change. It will therefore be the correct conclusion.

Feb 28, 2014 8:42am EST  --  Report as abuse
This discussion is now closed. We welcome comments on our articles for a limited period after their publication.