Radiation budget
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The radiation budget represents the balance between incoming energy from the Sun and outgoing thermal (longwave) and reflected (shortwave) energy from the Earth. The "budget" is an analogy between conservation of energy and household budgeting.
Globally, the budget is balanced: what is coming in is "spent" (otherwise the temperature would rise constantly). Locally, the budget is not balanced: tropical areas earn more than they spend, while at higher latitudes of the winter hemisphere more is spent than earned. The budgets are balanced by energy transfers in currents of ocean and atmosphere. For the transfers, radiation energy is transformed to latent heat, heat or even motion (kinetic energy), but in the end, it all becomes thermal energy and radiates off the Earth-Atmosphere system.
In the 1970s, the United States space agency NASA recognized the importance of improving their understanding of the radiation budget and its effects on the Earth's climate. Langley Research Center was charged with developing a new generation of instrumentation to make accurate regional and global measurements of the components of the radiation budget. The Goddard Space Flight Center built the Earth Radiation Budget Satellite (ERBS) on which the first ERBE instruments were launched by the Space Shuttle Challenger in 1984. ERBE instruments were also launched on two National Oceanic and Atmospheric Administration weather monitoring satellites, NOAA 9 and NOAA 10 in 1984 and 1986.
