Extreme weather to worsen with climate change: IPCC

KAMPALA Fri Nov 18, 2011 12:24pm EST

A man carrying his belongings wades through a flooded street in Nonthaburi province, on the outskirts of Bangkok November 18, 2011.  REUTERS/Chaiwat Subprasom

A man carrying his belongings wades through a flooded street in Nonthaburi province, on the outskirts of Bangkok November 18, 2011.

Credit: Reuters/Chaiwat Subprasom

KAMPALA (Reuters) - 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, U.N. scientists said on Friday.

The U.N. Intergovernmental Panel on Climate Change (IPCC) urged countries to come up with disaster management plans to adapt to the growing risk of extreme weather events linked to human-induced climate change, in a report released in Uganda on Friday.

The report gives differing probabilities for extreme weather events based on future greenhouse gas emissions scenarios, but the thrust is that extreme weather is likely to increase.

"It is virtually certain that increases in the frequency and magnitude of warm daily temperature extremes ... will occur in the 21st century on the global scale," the IPCC report said.

"It is very likely that the length, frequency and/or intensity of warm spells, or heat waves, will increase," it added.

"A 1-in-20 year hottest day is likely to become a 1-in-2 year event by the end of the 21st century in most regions," under one emissions scenario.

An exception is in very high latitudes, it said. Heat waves would likely get hotter by "1 degrees C to 3 degrees C by mid-21st century and by about 2 degrees C to 5 degrees C by late-21st century, depending on region and emissions scenario."

Delegates from nearly 200 countries will meet in South Africa from November 28 for climate talks with the most likely outcome modest steps toward a broader deal to cut greenhouse gas emissions to fight climate change.


The United Nations, the International Energy Agency and others say global pledges to curb emissions of CO2 and other greenhouse gases are not enough to prevent the planet heating up beyond 2 degrees Celsius, a threshold scientists say risks an unstable climate in which weather extremes become more common and food production more difficult.

Global carbon emissions rose by a record amount last year, rebounding on the heels of recession.

"It is likely that the frequency of heavy precipitation or the proportion of heavy rainfall from heavy falls will increase in the 21st century over many areas of the globe," especially in "high latitudes and tropical regions."

For the IPCC, "likely" means a two-thirds chance or more.

It said there was "medium confidence" that this would lead to "increases in local flooding in some regions", but that this could not be determined for river floods, whose causes are complicated.

The report said tropical cyclones were likely to become less frequent or stay the same, but the ones that do form are expected to be nastier.

"Heavy rainfalls associated with tropical cyclones are likely to increase with continued warming. Average tropical cyclone maximum wind speed is likely," the report said.

That, coupled with rising sea levels were a concern for small island states, the report said.

Droughts, perhaps the biggest worry for a world with a surging population to feed, were also expected to worsen.

The global population reached 7 billion last month and is expected to reach 9 billion by 2050, according to U.N. figures.

"There is medium confidence that droughts will intensify in the 21st century ... due to reduced precipitation and/or increased evapotranspiration," including in "southern Europe and the Mediterranean region, central Europe, central North America, Central America and Mexico, northeast Brazil and southern Africa."

There is a high chance that landslides would be triggered by shrinking glaciers and permafrost linked to climate change, it said.

(Writing and additional reporting by Tim Cocks; Editing by Janet Lawrence)

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Comments (2)
fastball wrote:
Where is the scientific proof that climate changes is human caused and not just the natural cycle of the earth? Yes we must be very aware of human pollution and try our best to control it, but I am tired of the scare tactics and the people getting very rich off these scare tactics and forcing changes that do nothing to lessen pollution but increases the costs for all.

Nov 18, 2011 1:33pm EST  --  Report as abuse
ScienceFreak wrote:
It has been a rough few years for the Anthropogenic Global Warming zealots with the Climategate revelations, uncooperative weather at every conference, and the recent BEST report which, instead of bolstering their case against mankind, indicates the planet stopped warming about 11 years ago despite rising co2 levels. And with three recent climate-related scientific discoveries that indicate the models used by the IPCC are woefully incomplete and fundamentally flawed, the politicians that run the IPCC are becoming desperate and have resulted to childish scare tactics to cram their social-engineering scheme disguised as science down our throats.

In the past 16 months we have discovered our atmosphere shrank during the nadir of our recent Solar Minimus and condensed by about 30% (NASA via CNN, July16, 2010). We also discovered that much more heat is lost into the outer atmosphere than climate models have been programmed to calculate (NASA via Forbes, July 27, 2010). Another blow to the religion of AGW came when CERN experiments confirmed Danish physicist Henrik Svensmark’s earlier work revealing that a primary driver of climate is cosmic radiation emanating from the sun and other celestial sources which stimulates the formation of heat-trapping clouds (CERN via The Telegraph, July 18, 2011). Each of these revelations held-up under peer review papers and each on their own put into question the level of understanding IPCC “scientists” actually possess regarding our climate.

There are many discoveries of lesser impact than the ones listed above but don’t expect the IPCC to admit they really don’t know enough to make bold predictions like the ones above. I would just like to know when the next ice-age is going to happen and why. I would also like to know what temperature it is supposed to be on earth. Hey IPCC, what say you?

AGW zealotry is not just a worldwide industry feathering the beds of all involved, it is also a backbone of global left-wing political movement which seeks to control each and every one of us for our own good. Some people have been fooled and are quite happy to give the socialists the keys to their lives. Lucky for them some of us are not.

Charles McFarling
Indianapolis, IN

Nov 18, 2011 3:17pm EST  --  Report as abuse
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