The first decade of the 21st century has been found to be the warmest ever with the global average surface temperature for that decade at 14.4°C.
In the northern hemisphere which includes majority of Asia and all of Europe, the years 1983-2012 has been found to be the warmest 30-year period of the last 1,400 years.
The Intergovernmental Panel on Climate Change's (IPCC) latest report has now confirmed that it is extremely likely (95-100% probability) that most of the warming since 1950 has been due to human influence. IPCC has predicted that by the year 2100, glacial volume would decline by as much as 35-85%.
According to the latest report released on Friday, it is now certain that the upper ocean (down to 700 metres) has warmed from 1971 to 2010.
The deep ocean below 3000 metres has also likely warmed since the 1990s, when sufficient observations became available.
Ocean warming accounts for most of the change in the amount of incoming solar energy stored by the Earth, accounting for about 93% of it between 1971 and 2010.
The global ocean will continue to warm during the 21st century. Heat will penetrate from the surface to the deep ocean and affect ocean circulation.
A crucial finding in the report is that the rate of sea level rise since the mid-19th century has been found to be larger than the mean rate during the previous two millennia.
The global mean sea level rose by around 19 cm from 1901 to 2010 due to increased ocean warming and melting glaciers and ice sheets.
The rate of rise accelerated between 1993 and 2010, and it is very likely to increase further during the 21st century and beyond.
The report notes that, during the last interglacial, when the climate was 2°C warmer than pre-industrial levels, maximum global sea levels were 5 to 10 meters higher than they are today.
Hence changes in extreme weather and climate events have been observed since about 1950. "It is very likely that the number of cold days and nights has decreased and the number of warm days and nights has increased on the global scale. In in large parts of Europe, Asia and Australia, it is likely that the frequency of heat waves has increased," IPCC said.
Seawater has become more acidic (its pH has decreased by 0.1) since the beginning of the industrial era due to humanity's carbon dioxide emissions; it will continue to acidify during the 21st century.
According to IPCC, the global mean average surface temperature rose by 0.89°C from 1901 to 2012. This means that each of the last three decades has been warmer than all preceding decades since 1850. IPCC has also predicted that global average temperatures will likely rise by another 0.3°C to 0.7°C in the period 2016-2035. Averaged over the period 2081-2100, the global surface temperature is likely to exceed pre-industrial levels by 1.5°C or even (depending on future greenhouse gas emissions) 2°C.
IPCC said "It is likely that human influences have affected the global water cycle and its patterns since 1960. For example, in recent decades precipitation has increased in the Northern Hemisphere".
Three years in the making, the "Physical Science Basis" volume of the Fifth Assessment Report was produced by over 250 scientists.
The new report further states that greenhouse gas emissions at or above current rates would induce changes in the oceans, ice caps, glaciers, the biosphere, and other components of theclimate system. Some of these changes would very likely be unprecedented over decades to thousands of years. Limiting climate change would require substantial and sustained reductions in emissions of carbon dioxide ( CO2) and other greenhouse gases.
In the northern hemisphere which includes majority of Asia and all of Europe, the years 1983-2012 has been found to be the warmest 30-year period of the last 1,400 years.
The Intergovernmental Panel on Climate Change's (IPCC) latest report has now confirmed that it is extremely likely (95-100% probability) that most of the warming since 1950 has been due to human influence. IPCC has predicted that by the year 2100, glacial volume would decline by as much as 35-85%.
According to the latest report released on Friday, it is now certain that the upper ocean (down to 700 metres) has warmed from 1971 to 2010.
The deep ocean below 3000 metres has also likely warmed since the 1990s, when sufficient observations became available.
Ocean warming accounts for most of the change in the amount of incoming solar energy stored by the Earth, accounting for about 93% of it between 1971 and 2010.
The global ocean will continue to warm during the 21st century. Heat will penetrate from the surface to the deep ocean and affect ocean circulation.
A crucial finding in the report is that the rate of sea level rise since the mid-19th century has been found to be larger than the mean rate during the previous two millennia.
The global mean sea level rose by around 19 cm from 1901 to 2010 due to increased ocean warming and melting glaciers and ice sheets.
The rate of rise accelerated between 1993 and 2010, and it is very likely to increase further during the 21st century and beyond.
The report notes that, during the last interglacial, when the climate was 2°C warmer than pre-industrial levels, maximum global sea levels were 5 to 10 meters higher than they are today.
Hence changes in extreme weather and climate events have been observed since about 1950. "It is very likely that the number of cold days and nights has decreased and the number of warm days and nights has increased on the global scale. In in large parts of Europe, Asia and Australia, it is likely that the frequency of heat waves has increased," IPCC said.
Seawater has become more acidic (its pH has decreased by 0.1) since the beginning of the industrial era due to humanity's carbon dioxide emissions; it will continue to acidify during the 21st century.
According to IPCC, the global mean average surface temperature rose by 0.89°C from 1901 to 2012. This means that each of the last three decades has been warmer than all preceding decades since 1850. IPCC has also predicted that global average temperatures will likely rise by another 0.3°C to 0.7°C in the period 2016-2035. Averaged over the period 2081-2100, the global surface temperature is likely to exceed pre-industrial levels by 1.5°C or even (depending on future greenhouse gas emissions) 2°C.
IPCC said "It is likely that human influences have affected the global water cycle and its patterns since 1960. For example, in recent decades precipitation has increased in the Northern Hemisphere".
Three years in the making, the "Physical Science Basis" volume of the Fifth Assessment Report was produced by over 250 scientists.
The new report further states that greenhouse gas emissions at or above current rates would induce changes in the oceans, ice caps, glaciers, the biosphere, and other components of theclimate system. Some of these changes would very likely be unprecedented over decades to thousands of years. Limiting climate change would require substantial and sustained reductions in emissions of carbon dioxide ( CO2) and other greenhouse gases.
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