Quote:
Originally Posted by Karl
The graphs posted by Bored Wombat show trends related to a "land - ocean" index while Prasham's second graph shows trends related to the lower troposphere.These are three separate, albeit (for climatological purposes) closely linked systems - the hydrosphere (water), the lithosphere (land + biomass), and the atmosphere.
For the purpose of temperature classification, the atmosphere has five (5) regions - the troposphere, stratosphere, mesosphere, thermosphere and exosphere. The graph refers to the troposphere - this is the region extending from sea level to the tropopause (which depending on conditions is between 7 km and 17 km above sea level). This is the lowest region of the atmosphere (closest to the ground) and it is within this zone that the biosphere is contained.
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Research suggests Upper Troposphere Warming
From:
physicsworld.com – May 28, 2008
Research performed in the US has provided insight on one of the lasting controversies surrounding climate models: whether or not the upper troposphere is warming. Climate models have long predicted that the upper troposphere — a region of the Earth’s atmosphere that lies beneath the stratosphere at an altitude of 10–12 km — should be warming at least as fast as the surface. However, since the 1970s temperature measurements carried out by weather balloons have found the lower-troposphere temperature to be fairly constant. This conclusion was backed up in 1990, when researchers used data taken from satellites to measure temperature changes in the troposphere.
Robert Allen and Steven Sherwood of Yale University have used wind data taken from weather balloons as a proxy for direct temperature measurements to give the first conclusive evidence that the upper troposphere has been warming after all. Although they are an indirect measure of temperature, these wind records can be backed up by satellite and ground instruments, making them more reliable than existing direct temperature measurements.
Wind data were obtained from 341 weather-balloon stations — 303 in the northern hemisphere and 38 in the southern hemisphere — covering a period from 1970 to 2005. The data were converted to temperature measurements, using a relationship known as the “thermal-wind equation”, which describes how vertical gradients in wind speed change with horizontally varying temperature. They found that the maximum warming has occurred in the upper troposphere above the tropics at
0.65 ± 0.47 °C per decade.
Full Article:
Upper troposphere is warming after all, research shows - physicsworld.com
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NB: Regardless of the validity or otherwise of the results, since it covers a period of 30+ years this qualifies as "climate research")