or Why scientists think the planet’s climate is changing
loosely speaking temperature is a measure of energy contained.
to find out temperature we need to measure the energy goes in and the energy goes out.
1827. found earth’s energy source is sun.
if energy does not goes out of earth it will heat up and burn up.
the hotter the object is the larger it loses energy.
input energy from the sun is fixed.
temperature goes up. one point the energy comes in matches with the energy goes out.
this is the equilibrium state.
since outer space is a vacuum only way for earth to loose energy is light radiation. ie electromagnetic radiation. infra red.
co2 is very good in absorbing infra red.
the higher you go up the thinner the atmosphere gets. so less GHG.
there is a level where the atmosphere gets thin enough that the radiation can escape to space. that is called radiating level.
for tjhe last 40 years tony williams (meteorologist) sending balloons to atmosphere twice a day. measurements are always different.
at 5000 m high energy begins to escape. temperature there is called radiating temperature of the planet.
if earth is radiating at -20C even after adding lot of co2 still it come to balance radiating at -20.
adding co2 is not changing radiating temp. but changing radiating altitude.
adding ghg the blanket became thicker. the energy escape happens in more higher altitude.
the more ghg you stuff in the atmosphere the higher you have to go before the atmosphere is thin enough to let the IR radiation escape to space.
tmp goes down 6C for each kilometer upward.
for a 6C warming you have to push the radiating level up to 1km.
to get 2C warming at surface you have need only to push the radiating level to 300 m. (1/3)
climate is so sensitive to the ghg concentration.
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1847 russian year book contains daily, monthly data from various places in russia.
after 1910 there is dramatic warming of temperature till 1940s. more in arctic region. after that till 1970s temperature cools slightly. and then warmed dramatically since.
mcmurdo sound, antarctica
andril, wekastitch . com
84m deep, then 850m deep in water down to sea floor. 1285m deep for 14 million years on sedimentary layers of rocks. temperature was 3C-4C higher.
arctic and antarctica was warm places.