Search results
Results from the WOW.Com Content Network
In 2002, Lean et al. [41] stated that while "There is ... growing empirical evidence for the Sun's role in climate change on multiple time scales including the 11-year cycle", "changes in terrestrial proxies of solar activity (such as the 14C and 10Be cosmogenic isotopes and the aa geomagnetic index) can occur in the absence of long-term (i.e ...
In addition to the density of incident light, the dissipation of light in the atmosphere is greater when it falls at a shallow angle. Figure 2 One sunbeam one mile wide shines on the ground at a 90° angle, and another at a 30° angle. The one at a shallower angle covers twice as much area with the same amount of light energy.
Another albedo-related effect on the climate is from black carbon particles. The size of this effect is difficult to quantify: the Intergovernmental Panel on Climate Change estimates that the global mean radiative forcing for black carbon aerosols from fossil fuels is +0.2 W m −2, with a range +0.1 to +0.4 W m −2. [63]
Some scientists say blocking a portion of the sun's rays could help buy humanity the time it needs to go green, but skeptics say the risks are too extreme to even consider the idea.
The albedo of several types of roofs (lower values means higher temperatures). Reflective surfaces, or ground-based albedo modification (GBAM), is a solar radiation management method of enhancing Earth's albedo (the ability to reflect the visible, infrared, and ultraviolet wavelengths of the Sun, reducing heat transfer to the surface).
The effect of Sun angle on climate results in the change in solar energy in summer and winter. For example, at latitudes of 65 degrees, this can vary by more than 25% as a result of Earth's orbital variation.
The scenarios for climate action required to meet 1.5 °C (2.7 °F) and 2 °C (3.6 °F) targets incorporate the predicted decrease in aerosol levels. [14] However, model simulations of the effects of aerosols on weather systems remain uncertain. [16] [17] The processes behind global dimming are similar to stratospheric aerosol injection.
The irradiance above the atmosphere also varies with time of year (because the distance to the Sun varies), although this effect is generally less significant compared to the effect of losses on DNI. Diffuse horizontal irradiance (DHI) , or diffuse sky radiation is the radiation at the Earth's surface from light scattered by the atmosphere.