There is increasing evidence that the amount of solar radiation incident at the Earth's surface is not stable over the years but undergoes significant decadal variations. Here I review the evidence for these changes, their magnitude, their possible causes, their representation in climate models, and their potential implications for climate change.
Particulate solar absorption is a critical factor in determining the value and even sign of the direct radiative forcing of aerosols. The heating to the atmosphere and cooling to the Earth's surface caused by this absorption are hypothesized to have significant climate impacts.
Rich nations should cut their greenhouse gas emissions by at least 40 percent by 2020 from 1990 levels as part of a new global climate change pact, China said on Thursday, spelling out its stance ahead of negotiations.
Photo: Shannon Stapleton
Boreal spring climate is uniquely susceptible to solar warming mechanisms because it has expansive snow cover and receives relatively strong insolation. Carbonaceous particles can influence snow coverage by warming the atmosphere, reducing surface-incident solar energy (dimming), and reducing snow reflectance after deposition (darkening).
WASHINGTON - Visibility on clear days has declined in much of the world since the 1970s thanks to a rise in airborne pollutants, scientists said on Thursday.
They described a "global dimming" in particular over south and east Asia, South America, Australia and Africa, while visibility remained relatively stable over North America and improved over Europe, the researchers said.
For India to harness the 5,000 trillion kWh equivalent energy that solar radiation makes available in a year, all that needs to be done is dedicate one per cent of the country
Meteorology plays an important role in the design, alignment and orientation of buildings, streets and urban colonies. Mitigative measures to ameliorate adverse impacts in tropical climates are suggested.
The observed increase in the concentration of greenhouse gases (GHGs) since the preindustrial era has most likely committed the world to a warming of 2.4°C (1.4°C to 4.3°C) above the preindustrial surface temperatures. The committed warming is inferred from the most recent Intergovernmental Panel on Climate Change (IPCC) estimates of the greenhouse forcing and climate sensitivity.
