data collection
* Header Source: Wildfire rages near Delta, California, in September 2018, stoked by relentless heat and drought. Article by Michael E Mann, “The weather amplifier – Strange waves in the jet stream foretell a future full of heat waves and floods”, Scientific American, March 2019, 37
One of the tasks of the Intergovernmental Panel on Climate Change (IPCC) is to assess and evaluate all relevant date on how the climate of the past hundred years or so has changed. Set out below is a small example of the kinds of exercise involved[1].
One of the tasks of the Intergovernmental Panel on Climate Change (IPCC) is to assess and evaluate all relevant date on how the climate of the past hundred years or so has changed. Set out below is a small example of the kinds of exercise involved[1].
a. This table provides examples of key observed changes and is not an exhaustive list. It includes both changes attributable to anthropogenic climate change and those that may be caused by natural variations or anthropogenic climate change.
The IPCC conclusions are that:
- warming is unequivocal, and since the 1850s many changes are unprecedented over decades to millennia.
- each of the last three decades has been successively warmer than any preceding decade since 1850.
- ocean warming accounts for more than 90% of the energy accumulated between 1971 and 2010.
- over the past two decades, Greenland and Antarctica ice sheets have lost mass, glaciers have shrunk and Arctic sea ice and Northern hemisphere spring snow cover have decreased.
- the rate of sea level rise has been larger than the mean rate for the previous 2,000 years (~19 cm since 1901).
- atmospheric CO2 concentrations are unprecedented in the last 800,000 years (+-40% since pre-industrial days)[2].
[1] Source: http://ipcc.ch/ipccreports/tar/vol4/index.php?idp=20 Intergovernmental panel on Climate change (IPCC): Climate Change 2001: Synthesis Report
[2] Associate Professor Michael Box’s summary at op cit 5.4.1.
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