Saturday, September 26, 2009

Impacts of Climate Change coming faster and sooner.


The pace and scale of climate change may now be outstripping even the most sobering predictions of the last report of the Intergovernmental Panel of Climate Change (IPCC).

An analysis of the very latest, peer-reviewed science indicates that many predictions at the upper end of the IPCC's forecasts are becoming ever more likely.

Meanwhile, the newly emerging science points to some events thought likely to occur in longer-term time horizons, as already happening or set to happen far sooner than had previously been thought.

Researchers have become increasingly concerned about ocean acidification linked with the absorption of carbon dioxide in seawater and the impact on shellfish and coral reefs.

Water that can corrode a shell-making substance called aragonite is already welling up along the California coast?decades earlier than existing models predict.

Losses from glaciers, ice-sheets and the Polar Regions appear to be happening faster than anticipated, with the Greenland ice sheet, for example, recently seeing melting some 60 percent higher than the previous record of 1998.

Some scientists are now warning that sea levels could rise by up to two metres by 2100 and five to ten times that over following centuries.

There is also growing concern among some scientists that thresholds or tipping points may now be reached in a matter of years or a few decades including dramatic changes to the Indian sub-continent's monsoon, the Sahara and West Africa monsoons, and climate systems affecting a critical ecosystem like the Amazon rainforest.

The report also underlines concern by scientists that the planet is now committed to some damaging and irreversible impacts as a result of the greenhouse gases already in the atmosphere.

Losses of tropical and temperate mountain glaciers affecting perhaps 20 percent to 25 percent of the human population in terms of drinking water, irrigation and hydro-power.

Shifts in the hydrological cycle resulting in the disappearance of regional climates with related losses of ecosystems, species and the spread of drylands northwards and southwards away from the equator.

Recent science suggests that it may still be possible to avoid the most catastrophic impacts of climate change. However, this will only happen if there is immediate, cohesive and decisive action to both cut emissions and assist vulnerable countries adapt.

These are among the findings of a report released today by the United Nations Environment Programme (UNEP) entitled Climate Change Science Compendium 2009.

The report, compiled in association with scientists around the world, comes with less than 80 days to go to the crucial UN climate convention meeting in Copenhagen, Denmark.

In a foreword to the document, the United Nations Secretary-General, Ban Ki-moon, who this week hosted heads of state in New York, writes, "This Climate Change Science Compendium is a wake-up call. The time for hesitation is over".

"We need the world to realize, once and for all, that the time to act is now and we must work together to address this monumental challenge. This is the moral challenge of our generation."

The Compendium reviews some 400 major scientific contributions to our understanding of Earth Systems and climate change that have been released through peer-reviewed literature, or from research institutions, over the last three years.

Achim Steiner, UN Under-Secretary General and UNEP Executive Director, said, "The Compendium can never replace the painstaking rigour of an IPCC process?a shining example of how the United Nations can provide a path to consensus among the sometimes differing views of more than 190 nations".

"However, scientific knowledge on climate change and forecasting of the likely impacts has been advancing rapidly since the landmark 2007 IPCC report," he added.

"Many governments have asked to be kept abreast of the latest findings. I am sure that this report fulfils that request and will inform ministers' decisions when they meet in the Danish capital in only a few weeks time," said Mr. Steiner.

The research findings and observations in the Compendium are divided into five categories: Earth Systems, Ice, Oceans, Ecosystems and Management. Key developments documented since the IPCC Fourth Assessment Report include:

Earth Systems

A new climate modeling system, forecasting average temperatures over a decade by combining natural variation with the impacts of human-induced climate change, projects that at least half of the 10 years following 2009 will exceed the warmest year currently on record. This is despite the fact that natural variation will partially offset the warming "signal" from greenhouse gas emissions.

The growth in carbon dioxide emissions from energy and industry has exceeded even the most fossil-fuel intensive scenario developed by the IPCC at the end of the 1990s. Global emissions were growing by 1.1 percent each year from 1990-1999 and this accelerated to 3.5 percent per year from 2000-2007.

The developing and least-developed economies, 80 percent of the world's population, accounted for 73 percent of the global growth of emissions in 2004. However, they contributed only 41 percent of total emissions, and just 23 percent of cumulative emissions since 1750.

Growth of the global economy in the early 2000s and an increase in its carbon intensity (emissions per unit of growth), combined with a decrease in the capacity of ecosystems on land and the oceans to act as carbon "sinks", have led to a rapid increase in the concentrations of carbon dioxide in the atmosphere. This has contributed to sooner-than-expected impacts including faster sea-level rise, ocean acidification, melting Arctic sea ice, warming of polar land masses, freshening of ocean currents and shifts in the circulation patterns of the oceans and atmosphere.

The observed increase in greenhouse gas concentrations are raising concern among some scientists that warming of between 1.4 and 4.3 degrees Centigrade above pre-industrial surface temperatures could occur. This exceeds the range of between 1 and 3 degrees perceived as the threshold for many "tipping points", including the end of summer Arctic sea ice, and the eventual melting of Himalayan glaciers and the Greenland ice sheet.

Ice

The melting of mountain glaciers appears to be accelerating, threatening the livelihoods of one fifth or more of the population who depend on glacier ice and seasonal snow for their water supply. For 30 reference glaciers in nine mountain ranges tracked by the World Glacier Monitoring Service, the mean rate of loss since 2000 has roughly doubled since the rate during the previous two decades. Current trends suggest that most glaciers will disappear from the Pyrenees by 2050 and from the mountains of tropical Africa by 2030.
In 2007, summer sea ice in the Arctic Ocean shrank to its smallest extent ever, 24 percent less than the previous record in 2005, and 34 percent less than the average minimum extent in the period 1970-2000. In 2008, the minimum ice extent was 9 percent greater than in 2007, but still the second lowest on record.
Until the summer of 2007, most models projected an ice-free September for the Arctic Ocean towards the end of the current century. Reconsideration based on current trends has led to speculation that this could occur as soon as 2030.

Melting of the Greenland Ice Sheet surface also seems to be accelerating. In the summer of 2007, the rate of melting was some 60 percent higher than the previous record in 1998.

The loss of ice from West Antarctica is estimated to have increased by 60 per cent in the decade to 2006, and by 140 percent from the Antarctic Peninsula in the same period.

Recent findings show that warming extends well to the south of the Antarctic Peninsula, to cover most of West Antarctica, an area of warming much larger than previously reported.

The hole in the ozone layer has had a cooling effect on Antarctica, and is partly responsible for masking expected warming on the continent. Recovery of stratospheric ozone, thanks to the phasing out of ozone-depleting substances, is projected to increase Antarctic temperatures in coming decades.

Oceans

Recent estimates of the combined impact of melting land-ice and thermal expansion of the oceans suggest a plausible average sea level rise of between 0.8 and 2.0 metres above the 1990 level by 2100. This compares with a projected rise of between 18 and 59 centimetres in the last IPCC report, which did not include an estimate of large-scale changes in ice-melt rates, due to lack of consensus.

Oceans are becoming more acidic more quickly than expected, jeopardizing the ability of shellfish and corals to form their external skeletons. Water that can corrode a shell-making carbonate substance called aragonite is already welling up during the summer along the California coast, decades earlier than models predict.

Ecosystems

Since the 2007 IPCC report, wide-ranging surveys have shown changes to the seasonal behaviour and distribution of all well-studied marine, freshwater and terrestrial groups of plants and animals. Polar and mountaintop species have seen severe contractions of their ranges.
A recent study projecting the impacts of climate change on the pattern of marine biodiversity suggests dramatic changes to come. Ecosystems in sub-polar waters, the tropics and semi-enclosed seas are predicted to suffer numerous extinctions by 2050, while the Arctic and Southern Oceans will experience severe species invasions. Marine ecosystems as a whole may see a species turnover of up to 60 percent.

Under the IPCC scenario that most closely matches current trends ? i.e. with the highest projected emissions ? between 12 and 39 percent of the Earth's land surface could experience previously unknown climate conditions by 2100. A similar proportion, between 10 and 48 percent, will see existing climates disappear. Many of these "disappearing climates" coincide with biodiversity hotspots, and with the added problem of fragmented habitats and physical obstructions to migration, it is feared many species will struggle to adapt to the new conditions.
Perennial drought conditions have already been observed in South-eastern Australia and South-western North America. Projections suggest that persistent water scarcity will increase in a number of regions in coming years, including southern and northern Africa, the Mediterranean, much of the Middle East, a broad band in Central Asia and the Indian subcontinent.

Management

The reality of a rapidly-changing climate may make conventional approaches to conservation and restoration of habitats ineffective. Drastic measures such as large-scale translocation or assisted colonization of species may need to be considered.
Eco-agriculture, in which landscapes are managed to sustain a range of ecosystem services, including food production, may need to replace the current segregation of land use between conservation and production. This could help create resilient agricultural ecosystems better able to adapt to the changing climate conditions.

Experts increasingly agree that active protection of tropical forests is a cost-effective means of cutting global emissions. An international mechanism of reducing emissions from deforestation and forest degradation (REDD) is likely to emerge as a central component of a new agreement in Copenhagen. However, many issues need to be resolved, such as how to verify the reductions and ensuring fair treatment of local and indigenous forest communities.

A number of innovative approaches are emerging to keep carbon out of the atmosphere, including the use of "biochar", biologically-derived charcoal. It is mixed in soils, increasing fertility and potentially locking up carbon for centuries. This is a 21st century application of a technology known as Terra Preta, or Black Earth, used by Amazon peoples before the arrival of Europeans in South America.


Ref: IPCC Website

10 comments:

Zheng junxai5 said...

2015-07-24 zhengjx
jordan femme
coach factory outlet
toms shoes for women
burberry outlet online
oakley sunglasses outlet
kate spade handbags
oakley store
soccer shoes for sale
replica watches for sale
true religion
cheap oakley sunglasses
ray bans
chanel outlet
coach outlet online
ralph lauren sale
longchamp
ray ban outlet
nike blazer pas cher
burberry outlet
oakley sunglasses cheap
oakley sunglasses outlet
cheap oakleys
michael kors bags
ed hardy clothing outlet
longchamp pas cher
fitflops shoes
coach outlet store online
pandora jewelry stores
ray ban glasses
coach factory outlet
fitflops shoes
louboutin pas cher
burberry sale
ed hardy uk
soccer jerseys for sale
michael kors handbags
nike blazer low pas cher
michael kors uk outlet
gucci handbags
michael kors handbags

ninest123 Ninest said...

ninest123 12.03
mulberry, hollister, nike free pas cher, true religion jeans, polo ralph lauren, sac burberry, vanessa bruno, coach outlet store online, north face, michael kors pas cher, converse pas cher, lululemon outlet online, nike free, ralph lauren, sac guess, true religion outlet, abercrombie and fitch, hogan outlet, sac hermes, ray ban pas cher, sac longchamp pas cher, coach factory outlet, longchamp, hollister, timberland, vans pas cher, air max, air max pas cher, michael kors uk, louboutin, air jordan, nike huaraches, nike roshe, true religion jeans, michael kors, north face, longchamp, polo lacoste, nike roshe run pas cher, new balance pas cher, air max, ray ban sunglasses, nike air max, nike tn, true religion outlet, nike air force, coach purses, michael kors outlet, nike blazer, oakley pas cher, nike trainers

ninest123 Ninest said...

air max, oakley sunglasses, louis vuitton outlet, cheap uggs, prada outlet, louis vuitton, gucci outlet, polo ralph lauren outlet, chanel handbags, tiffany and co, ugg boots clearance, burberry outlet, louboutin outlet, polo ralph lauren, rolex watches, michael kors outlet, ray ban sunglasses, michael kors outlet online sale, ray ban sunglasses, jordan shoes, replica watches, michael kors outlet, oakley sunglasses, air max, nike shoes, louboutin shoes, michael kors outlet, longchamp handbags, prada handbags, uggs, louis vuitton outlet, burberry outlet, louboutin, cheap oakley sunglasses, oakley sunglasses cheap, ray ban sunglasses, longchamp outlet, longchamp handbags, nike free, michael kors outlet, tory burch outlet, louis vuitton outlet stores, ugg outlet, christian louboutin, oakley sunglasses, uggs outlet, louis vuitton handbags, tiffany and co, michael kors outlet

ninest123 Ninest said...

soccer jerseys, celine handbags, hollister clothing store, iphone 5s cases, ipad cases, louboutin, gucci, converse, nike roshe run, iphone 6 plus cases, new balance shoes, jimmy choo outlet, abercrombie and fitch, abercrombie, vans, bottega veneta, iphone 6s plus cases, birkin bag, instyler, asics running shoes, herve leger, ghd, s6 case, ralph lauren, vans shoes, nfl jerseys, iphone cases, baseball bats, wedding dresses, reebok outlet, mac cosmetics, ray ban, valentino shoes, giuseppe zanotti, timberland boots, insanity workout, mcm handbags, north face outlet, north face jackets, chi flat iron, ferragamo shoes, air max, beats by dre, babyliss pro, lululemon outlet, soccer shoes, mont blanc, iphone 6s cases, p90x, air max, iphone 6 cases, oakley

ninest123 Ninest said...

canada goose, swarovski crystal, louis vuitton uk, moncler, toms shoes, ugg boots, juicy couture, karen millen, rolex watches, moncler, ugg pas cher, pandora charms, sac louis vuitton, louis vuitton, canada goose uk, converse shoes, pandora jewelry, moncler, moncler, sac lancel, juicy couture outlet, moncler, supra shoes, thomas sabo, moncler, barbour, doke gabbana, sac louis vuitton, ugg, canada goose jackets, coach outlet store online, canada goose, canada goose, swarovski, pandora jewelry, ugg, moncler, canada goose, links of london, canada goose, canada goose outlet, montre homme, pandora charms, hollister, barbour, moncler outlet, marc jacobs, louis vuitton, wedding dresses, ugg
ninest123 12.03

Cran Kate said...

Michael Kors Outlet Ralph Lauren Outlet Gucci Factory Outlet Gucci Outlet Gucci Handbags Cheap Ray Ban Sunglasses North Face Jackets Prada Outlet Burberry Outlet Hollister Clothing Ferragamo Shoes Tiffany Jewelry Tiffany Outlet NFL Jerseys Cheap Jordans Oakley Outlet North Face Outlet Burberry Outlet Ray Ban Sunglasses
Chan Luu Sale Toms Outlet Burberry Outlet Oakley Sunglasses Toms Shoes Sale Beats By Dr Dre Coach Outlet Christian Louboutin Shoes Oakley Sunglasses Valentino Shoes
Oakley Eyeglasses Michael Kors Outlet Coach Factory Outlet Coach Outlet Online Coach Purses Kate Spade Outlet Toms Shoes North Face Outlet Coach Outlet Gucci Belt

艾丰 said...

jianbin0314
michael kors outlet online
hollister canada
mcm outlet
nike air max
michael kors outlet online
air max 2015
rolex watches
camisetas futbol baratas
michael kors outlet sale
michael kors outlet
giuseppe zanotti outlet
michael kors wallet sale
coach outlet store
abercrombie and fitch
kobe 9
true religion outlet
coach outlet online
nike huarache
basketball shoes
cheap nfl jerseys
louis vuitton handbags
lacoste shirts
ray ban sunglasses
nike outlet store
michael kors canada
nike air max uk
michael kors handbags
true religion jeans
calvin klein outlet
tods outlet
nike roshe run
michael kors outlet online
michael kors outlet
christian louboutin uk
christian louboutin shoes
michael kors outlet

Cran Kate said...

Burberry Belt Tory Burch Boots Louis Vuitton Belt Ferragamo Belt Marc Jacobs Handbags Lululemon Outlet Christian Louboutin Shoes True Religion Outlet Tommy Hilfiger Outlet
Michael Kors Outlet Coach Outlet Red Bottoms Kevin Durant Shoes New Balance Outlet Adidas Outlet Coach Outlet Online Stephen Curry Jersey Vans Outlet Ralph Lauren Outlet
Ugg Boots Sale UGGS For Women Skechers Go Walk Adidas Yeezy Boost Adidas Yeezy Adidas NMD Coach Outlet North Face Outlet Ralph Lauren Outlet Puma Outlet Polo Outlet
Under Armour Outlet Under Armour Hoodies Herve Leger MCM Belt Nike Air Max Louboutin Heels Jordan Retro 11 Converse Outlet Nike Roshe Run UGGS Outlet North Face Outlet

Gege Dai said...

replica watches
swarovski jewelry
rolex orologi
cheap snapbacks
louboutin pas cher
louis vuitton bags cheap
michael kors outlet online
canada goose outlet
replica watches
tory burch outlet online
tiffany jewelry
converse shoes sale
michael kors outlet clearance
mulberry outlet
tory burch outlet
pandora jewelry
tods shoes
nike air max
cartier sunglasses
nike foamposite
michael kors handbags
michael kors handbags
longchamp outlet online
calvin klein outlet
mulberry outlet
nike huarache
ray-ban sunglasses
ray ban sunglasses sale
nike store uk
ray ban sunglasses
ralph lauren femme
cheap ugg boots
ray ban sunglasses
moncler coats
michael kors outlet
louis vuitton outlet store
0808jianxiang

Blogger said...

I have just installed iStripper, and now I enjoy having the hottest virtual strippers on my desktop.

New and Renewable Energy

New and Renewable Energy
Your source for the New and Renewable Energy News and Technologies