Global warming not stopped, will go on for centuries - WMO

March 24, 2014 by admin  
Filed under Global Warming


GENEVA (Reuters) - There has been no reverse in the trend of global warming and there is still consistent evidence for man-made climate change, the head of the U.N. World Meteorological Organisation (WMO) said on Monday.

A slow-down in the average pace of warming at the planet’s surface this century has been cited by “climate sceptics” as evidence that climate change is not happening at the potentially catastrophic rate predicted by a U.N. panel of scientists.

But U.N. weather agency chief Michel Jarraud said ocean temperatures, in particular, were rising fast, and extreme weather events, forecast by climate scientists, showed climate change was inevitable for the coming centuries.

“There is no standstill in global warming,” Jarraud said as he presented the WMO’s annual review of the world’s climate which concluded that 2013 tied with 2007 as the sixth hottest year since 1850 when recording of annual figures began.

“The warming of our oceans has accelerated, and at lower depths. More than 90 percent of the excess energy trapped by greenhouse gases is stored in the oceans.

“Levels of these greenhouse gases are at a record, meaning that our atmosphere and oceans will continue to warm for centuries to come. The laws of physics are non-negotiable,” Jarraud told a news conference.

The 21-page survey said the global land and sea surface temperature in 2013 was 14.5 degrees Celsius (58.1 Fahrenheit), or 0.50C (0.90F) above the 1961-90 average. It was also 0.03C (0.05F) up on the average for 2001-2010.

The WMO’s Annual Statement on the Status of the Climate, pointed to droughts, heatwaves, rising seas, floods and tropical cyclones around the globe last year as evidence of what the future might hold.

FLUCTUATIONS

It was issued on the eve of a conference bringing climate scientists together with officials from over 100 governments in Japan from March 25-29 to approve a report on the effects of future global warming and how these might be mitigated.

A draft of this report, from the Intergovernmental Panel on Climate Change (IPCC), says global warming will disrupt food supplies, slow world economic growth and may already be causing irreversible damage to nature.

The chair of the IPCC, Rajendra Pachauri, told Reuters last week that the report made even more compelling the scientific arguments for a reduction in greenhouse gas emissions.

Some 200 countries have agreed to try to limit global warming to less than 2.0 degrees Celsius above pre-industrial times, largely by cutting emissions from burning fossil fuels like coal, oil and gas.

Sceptics argue that changes in global weather are the product of natural fluctuations or other natural causes.

But such arguments were rejected by Jarraud.

Natural phenomena like volcanoes or the El Nino/La Nina weather patterns originating in Pacific Ocean temperature changes had always framed the planet’s climate, affecting heat levels and disasters like drought and floods, he said.

“But many of the extreme events of 2013 were consistent with what we would expect as a result of human-induced climate change,” declared the WMO chief, pointing to the destruction wreaked by Typhoon Haiyan in the Philippines.

Another example was the record hot summer of 2012-13 in Australia which brought huge bush fires and destruction of property. Computer simulations showed the heat wave was 5 times as likely under human influence on climate, Jarraud said.

Among other extreme events of 2013 probably due to climate change were winter freezes in the U.S. south-east and Europe, heavy rains and floods in north-east China and eastern Russia, snow across the Middle East and drought in south-east Africa.

(Editing by Robin Pomeroy)

Article source: http://in.reuters.com/article/2014/03/25/climatechange-temperature-idINDEEA2O00620140325

Yes, Manmade Global Warming Is Worsening California’s Epic Drought

March 23, 2014 by admin  
Filed under Global Warming


By Joe Romm on

March 23, 2014 at 1:29 pm

California’s epic drought got even worse last week. The U.S. Drought Monitor reports that the area of California under moderate drought (or worse) rose from 94.6 percent of the state to a stunning 99.8 percent. The area under extreme or exceptional drought rose from 65.9 to 71.8 percent, encompassing the entire agriculture-rich Central Valley

Back in January, we interviewed 8 of the leading climate and drought experts in the country, who explained in great detail how climate change is worsening California’s epic drought in multiple ways. As I discussed in my 2011 literature review in the journal Nature — even in regions where climate change does not alter the amount of precipitation, it will have these effects:

What precipitation there is will probably come in extreme deluges, resulting in runoff rather than drought alleviation. Warming causes greater evaporation and, once the ground is dry, the Sun’s energy goes into baking the soil, leading to a further increase in air temperature…. Finally, many regions are expected to see earlier snowmelt, so less water will be stored on mountain tops for the summer dry season.

The president’s science advisor John Holdren made precisely the same points in a recent paper.

These points are disputed by very few. So why is there any confusion? A relatively small subset of experts are focused very narrowly on the issue of whether global warming caused a reduction in precipitation — but they generally fail to make clear how narrow their perspective is. NOAA’s Martin Hoerling did this in a recent New York Times piece, asserting “At present, the scientific evidence does not support an argument that the drought there is appreciably linked to human-induced climate change.”

Now, in fact, there is science supporting the argument that the reduction in precipitation is directly linked to human-induced climate change, specifically Arctic ice loss. I broke that story last June (see here) and updated it again in March.

But even setting aside the precipitation issue, our leading scientists have repeatedly made clear that global warming is worsening the drought. In a letter to the NY Times, three top drought experts — Peter Gleick, Jonathan Overpeck, and Connie Woodhouse — explain that the issue of what “caused” the drought “is the wrong question to ask”:

The current drought has certainly been exacerbated by climate change for one simple reason: Temperatures in California are now higher today, as they are globally. This alone increases water demand by crops and ecosystems, accelerates snowpack loss, and worsens evaporation from reservoirs. There are other complicating effects, but the influence of higher temperatures on drought is already real and cannot be ignored.

We are now unambiguously altering the climate, threatening water supplies for human and natural systems. This is but one example of how even today we are paying the cost of unavoidable climate changes.

As if to underscore this point, last week NOAA released its climate analysis of the U.S. winter, reporting:

California had its warmest winter on record…. The California winter temperature was 48.0°F, 4.4°F above the 20th century average, far exceeding the previous record, set in 1980/81, by 0.8°F.

And as Tamino explains, in California, “If we look at an actual measure of drought — the Palmer Drought Severity Index, or PDSI — then there is a decreasing trend (which means, toward more and/or more extreme drought) which is statistically significant.”

Finally, our favorite climate videographer Peter Sinclair has interviewed a variety of scientists on this subject in yet another must-see video:

Article source: http://thinkprogress.org/climate/2014/03/23/3417814/global-warming-california-drought/