NASA has successfully launched the climate satellite named “Ready, Aim, PREFIRE,” to study heat emissions at Earth’s poles.
What is the PREFIRE mission?
PREFIRE stands for “Polar Radiant Energy in the Far-InfraRed Experiment”.
The mission consists of two shoebox-sized CubeSats, each equipped with a Thermal Infrared Spectrometer capable of measuring the far-infrared radiation emitted by the Earth’s coldest and most remote regions.
The satellite launched is one of the two climate satellites that are part of the PREFIRE mission.
The other is “PREFIRE and ICE,” and will be launched in the coming days.
Significance
Its observations will help in understanding the fundamentals of Earth’s heat balance, allowing us to better predict how ice, seas, and weather will change in the face of global warming.
The mission also focuses on heat emitted as far-infrared radiation by the Arctic and Antarctica, which is currently not measured in detail.
Heat Budget of Earth
A heat budget is a perfect balance between incoming heat (insolation) absorbed by the earth and outgoing heat (terrestrial radiation) escaping it in the form of radiation.
The equilibrium that exists between the insolation (short waves) and the terrestrial radiation (long waves) is called the heat budget of the earth.
Explanation of Heat Budget
Let’s consider that the top of the atmosphere receives 100% of the insolation.
Approximately 35 units of insolation are reflected into space before even reaching the Earth’s surface. Out of these, 27 units are reflected from the top of clouds, and 2 units are reflected from snow and ice-covered areas.
The reflected radiation is referred to as the Earth’s albedo.
The remaining 65 units of insolation are absorbed, with 14 units absorbed within the atmosphere and 51 units absorbed by the Earth’s surface. The Earth then radiates back 51 units of terrestrial radiation.
Out of these, 17 units are radiated directly into space, while the remaining 34 units are absorbed by the atmosphere.
Additionally, 48 units absorbed by the atmosphere are also radiated back into space.
Therefore, the total radiation returning from the Earth and the atmosphere is 17 + 48 = 65 units, which balances the total of 65 units received from the Sun.
Impacts of Imbalance of Heat Budget
Rising Global Temperatures: Increased greenhouse gases trap more heat in the atmosphere, leading to higher global temperatures.
Melting Polar Ice and Glaciers: Warmer temperatures cause ice sheets and glaciers to melt, contributing to rising sea levels.
Higher sea levels erode coastlines and increase the frequency and severity of coastal flooding.
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Ocean Warming: The ocean absorbs most of the excess heat, leading to thermal expansion and further sea level rise.
Coastal and marine habitats, such as mangroves and coral reefs, are threatened by rising waters.
Increased Frequency of Heatwaves: Prolonged periods of excessive heat become more common.
Ocean Acidification: Higher levels of carbon dioxide dissolved in ocean water will lead to acidification.
Acidic waters harm calcifying organisms like corals, mollusks, and some plankton species, disrupting marine ecosystems.
