How a Balance Between Incoming Solar Radiation and Outgoing Longwave Radiation Must Be Maintained in Order to Keep Annual Temperatures the Same
When it reaches the Earth, some is reflected back to space by clouds, some is absorbed by the atmosphere, and some is absorbed at the Earth's surface.
According to Planck’s law of radiation electromagnetic waves emitted by the surface of the Earth and by the atmosphere, which have a temperature of 200-300 K, have a much larger wavelength and lower frequency than the electromagnetic waves emitted by the Sun, which has a surface temperature of 5780 K. For this reason, the radiation emitted by the Earth and by the atmosphere is generally referred to as “long-wave” radiation, while Solar radiation is referred to as “short-wave” radiation. While short-wave radiation is transmitted through the atmosphere almost unattenuated, longwave radiation is strongly absorbed and re-emitted by water vapour, carbon dioxide and other trace gases in the air.
Climate and thermodynamic systems of maximum dissipation). The solar radiation flux maintains the atmosphere in a non-equilibrium thermodynamics situation, generating a climate dynamics which has an influence on the temperature of the planet. Changes in the energy balance of the atmosphere are the drivers of climate change. Nowadays, it is believed that the Earth absorbs more energy from the Sun than it is emitted to the space, creating a situation of energy imbalance (Hansen, J. et al. Earth’s energy imbalance: Confirmation and implications). Although those differences can be monitored from the ground, the use of satellite sensors to provide measures of the fluxes of energy to and from Earth offers a more precise view of the system. The evolution of the energy imbalance has been investigated using satellite data and models, and it seems to be increasing in the last decades (Loeb, N. G. et al. Toward optimal closure of the earth’s top-of-atmosphere radiation budget).
Given the monumental challenge and uncertainties associated with a major mitigation program, the authors would like to advise to consider all available and emerging technologies. This suggests fundamental research on new MR energy technologies in addition to those already known in order to become part of the global research portfolio, since breakthroughs on today's embryonic technologies could yield tomorrow's alternatives.
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