The United Nations panel experience as the Intergovernmental Panel on Climate Change meet once every six years , look back the late independent analysese   of climate variety using lineal observations of Earth ’s climate , palaeoclimate archive , theoretic studies of climate processes and simulations using climate models . The 95 percent foregone conclusion that humans have induce most of the warming of the planet ’s control surface is an increase in certainty from the 90 per centum foregone conclusion in the last judgment study , which came out in 2007 .

The Summary for Policymakers of the IPCC ’s Fifth Assessment Report was liberate September 27 , and warns that a pause in warming over the past 15 years is too short to shine farseeing - term trends . Present - 24-hour interval carbon dioxide levels are at an " unprecedented " grade which has not been seen for at least the last 800,000 years . proceed emission of greenhouse gasoline like carbon dioxide will cause further warming and changes in all aspect of the mood system of rules . comprise these changes will require free burning reductions of nursery gas emissions .

ocean spirit level is also place to continue to rise up at a faster charge per unit than over the past 40 geezerhood , with water levels expected to wax between 26 centimeter at the dispirited end and 82 cm at the high terminal . Over the last twenty years the Greenland and Antarctic shabu rag have been melting , glacier have receded in most part of the existence , and Arctic sea ice has continued to flinch in terms of extent .

The Arctic has lost 75 per centum of its summer sea ice mass

Last year ’s Arctic   sea ice   minimum exceeded the old record low , with the water ice declining the previous two years as well ; this year there has been a brusque - term ' recovery' . The Arctic has lost 75 percent of its summertime sea ice volumeover the past three decades and climatologists are not just concerned about the extent of the ocean trash , but also its thickness , which has been in constant declination . Each twelvemonth the Arctic ocean ice hit its minimum in September . Arctic sea ice extent reached its lowest full point this class on September 13 , 2013 when ocean Methedrine extent dropped to 5.10 million square kilometres . September averaged an sparkler extent of 5.35 million straightforward kilometres , placing 2013 as the sixth lowest ice extent , both for the daily minimum extent and the monthly norm . September ice extent was 1.17 million square kilometres below the 1981 to 2010 average .

ocean ice in Antarctica reached a winter maximal extent of 19.47 million square kilometres this year . Antarctic sea meth extent for August 2013 averaged 6.09 million square kilometres , which was 1.03 million square klick below the 1981 to 2010 norm for August , but above the tier put down last year . 2012 had the lowest September ice extent in the satellite phonograph recording . In any make year the weather can act to either keep more or unthaw more ocean ice at both pole .

The Arctic methamphetamine detonating equipment grows each wintertime as the sun sets for several months and head-shrinker each summertime as the sun rise higher in the northerly sky . Each year the Arctic ocean ice strain its annual minimal extent in September . It hit a new record Sir David Alexander Cecil Low in 2012 . This summertime ’s low ice extent preserve the downward trend seen over the last thirty - four class . scientist attribute this drift in large part to warming temperature triggered by climate modification . Since 1979 , September Arctic sea crank extent has declined by 13.7 percent per decade . Summer ocean icing extent is of import because , among other things , it reflects sunshine , keeping the Arctic region cool and tame global climate .

Each of the last three decennary has been warmer at the Earth ’s surface , warmer than any period since 1850 , and most potential warmer than any sentence in the preceding 1,400 year . Model simulations indicate that the change in the global open temperature by the last of the 21st Century is likely to exceed 1.5 degree Celsius , relative to 1850 .

The new paper alters one figure from the 2007 report : the temperature range give for a double of CO2 in the atmosphere was 2.0C - 4.5C in the 2007 report and this range has been change to 1.5C - 4.5C.

This telecasting depicts a scenario in which carbon dioxide concentrations get hold of 670 parts per million by 2100 , up from around 400 ppm today : http://bit.ly/1h8zPg9

Sources :

The IPCC Summary for Policymakers : http://bit.ly/15UJlPg

IPCC : http://bit.ly/1a3HJUm

National Snow and Ice Data Center : http://bit.ly/15OwqE2

NASA : http://1.usa.gov / GFWHZr;http://1.usa.gov/198nQu6