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https://phys.org/news/2023-05-earth-energy.html
A recent report from the World Meteorological Organization about the state of the climate indicates that the global mean temperature in 2022 was 1.15°C above the 1850-1900 (preindustrial reference period) average. Moreover, the last eight years have been the warmest since the beginning of instrumental temperature records 173 years ago.
In other words, the climate system has been out of balance for several decades.
[...] Earth's energy imbalance -- Solar radiation is virtually Earth's only energy source, the other energy sources—such as Earth's interior heat and tidal energy—being negligible. The Earth reflects around 30 percent of the solar radiation and emits radiation towards space.
The greenhouse gases (carbon dioxide, methane) let solar radiation pass, but not the radiation emitted by the Earth, thus trapping this energy. Earth's near-surface temperature, which is 15°C, would be around -19°C without the greenhouse effect.
If the difference between the incoming energy—solar radiation—and outgoing energy—the sum of the solar radiation reflected by the Earth and the radiation emitted by the Earth—is not equal to zero, as is the case currently, we refer to this as Earth Energy Imbalance (EEI).
It is human activity, through the emission of greenhouse gases (generating an additional greenhouse effect), that has caused the Earth energy imbalance.
But where does the excess energy accumulate? It accumulates under the form of heat in the different components of the climate system (atmosphere, land, hydrosphere, cryosphere, biosphere). And this is what explains why the Earth is warming, or more globally, climate change.
Such an inventory corresponding to the period 1960-2020 has been provided by a recently published study. This study shows that the Earth system has been accumulating heat since 1971. Moreover, the rate of heat accumulation corresponding to the period 2006-2020 is higher than that corresponding to 1971-2020. Most of the excess heat is stored in the ocean (89 percent), mainly in the upper ocean (0-700 metres in depth). The rest of the excess heat is stored in the land (six percent) and the atmosphere (one percent), and has led to the melting of the components of the cryosphere—glaciers, ice sheets and sea ice (four percent).
In addition to storing excess heat, the ocean is also an important CO₂ sink, thus playing an essential role in the regulation of the climate. However, the ocean will become less efficient at capturing CO₂ with the increase in the cumulative emissions of this gas. Why? Because of the positive feedback between the ocean warming and the decrease in the capacity of the oceans to absorb CO₂.
Unfortunately, the current state of the ocean is concerning. In 2022, the ocean heat content reached a record high, and 58 percent of the ocean surface experienced at least one marine heatwave. Since mid-March this year, the mean ocean surface temperature is the highest ever observed since the beginning of the satellite era. Among other negative impacts on the marine ecosystems, marine heatwaves cause coral bleaching events.
(Score: 2, Interesting) by JoeMerchant on Thursday June 01 2023, @01:11PM
>Something isn't ringing true with me. Unless Venus is getting energy from somewhere else.
I'm going to go with: it's the surface temperature that's hotter on Venus, and it works like this with the greenhouse gasses:
Your solar radiation passes through CO2 and similar layers like an AC signal passes a band-stop filter when it's out of the stop-band.
Then, something magic (frequency shift) happens on the surface of the planet. This isn't typically possible, or at least easy, in simple LRC circuits, but that incoming solar radiation is absorbed and then re-radiated at a different frequency, and that frequency _does_ match the stop-band frequency of the CO2 layer and so it is impeded from returning to space and remains hanging out on the surface of Venus (and, to a lesser degree, the Earth).
The top few miles of the lithosphere are apparently a really good thermal insulator, so what happens on the surface thermally pretty much stays on the surface. Earth has a thermal storage battery in the oceans, Venus managed to boil hers up into the atmosphere so they don't work the same as our liquid thermal bank.
Consider that the oceans average 2 miles deep, 1.3 miles deep if you were to spread them across all the land. Think about the thermal capacity of 1.3 miles of water just in a column over your house. What would it take to shift that water from its average temperature of 4C up to 5C? There's over 15 acres of earth surface area per human, even today with over 8 billion humans, so your personal share of earth's water works out to 20.4 acre-miles, or 107,700 acre feet or 1.33 * 10^11 liters of water, per person. It takes 1000 calories (239 J / 1.16kWh) to heat a liter of water 1C. So, the takeaway of this 1.33 * 10^11 liters of water per person is: temperature change of the oceans takes a LOT of energy, decades of accumulation to make it noticeably warmer, decades of decay to make it noticeably cooler.
Across centuries of change in one direction or another, the results can be Venusianly dramatic.
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