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  • Earth’s atmosphere uses solar energy to run a so-called ‘heat engine’
  • This engine circulates air and heat, and is ultimately responsible for storms
  • Experts have studied how climate change impacts how this engine works
  • They compared records from 1981 to 2012 with simulations up to 2098
  • Third of the energy is involved with water moving through the atmosphere
  • But, climate change causes the atmosphere to use more energy during this part of the cycle, which creates more evaporation and precipitation
  • This limits how much energy is used as part of the circulation cycle
  • Atmosphere still needs to get rid of the precipitation it collects, but subsequently has to do it in fewer, more intense storms

By Victoria Woollaston for MailOnline

Published: 12:41 EST, 2 February 2015 | Updated: 12:50 EST, 2 February 2015

For years, scientists have predicted that as global warming heats the Earth, the number of storms will increase.

But, new research suggests that instead of increasing in number, these storms will increase in intensity – meaning the same number of storms will occur, but they’ll be stronger.

The physicists said that this is because global warming will directly affect how the atmosphere circulates air mass, heat and water using what’s been dubbed ‘Earth’s heat engine.’

Experts from the University of Toronto predict that as the Earth becomes warmer, as a result of climate change, the number of storms will remain the same, but the intensity will increase. This is because global warming will directly affect how heat, air mass and water circulates through the atmosphere

Researchers from the University of Toronto explained that the Earth’s atmosphere needs fuel to work, which in this instance is energy from the sun.

As air is warmed by the sun and moves closer to the Equator, the air mass near the surface ‘absorbs’ water through evaporation.

The warmer the air mass, the more water it takes up, and as it reaches the Equator, it begins to rise through the atmosphere, eventually cooling as it radiates heat out into space.

Cool air typically holds less moisture than warm air, so as the air cools, condensation occurs, and heat is released.

When enough heat is released, air begins to rise even further, pulling more air behind it, which ultimately causes a thunderstorm.

EARTH’S ‘GIANT HEAT ENGINE’

Researchers from the University of Toronto explained that the Earth’s atmosphere needs fuel to work, which in this instance is energy from the sun.

As air is warmed by the sun and moves closer to the Equator, the air mass near the surface ‘absorbs’ water through evaporation.

The warmer the air mass, the more water it takes up, and as it reaches the Equator, it begins to rise through the atmosphere, eventually cooling as it radiates heat out into space.

Cool air typically holds less moisture than warm air, so as the air cools, condensation occurs, and heat is released.

When enough heat is released, air begins to rise even further, pulling more air behind it, which ultimately causes a thunderstorm.

The ‘output’ of this atmospheric engine, and storms, is the amount of heat and moisture that is redistributed between the Equator and the North and South Poles.

The ‘output’ of this atmospheric engine, and storms, is the amount of heat and moisture that is redistributed between the Equator and the North and South Poles.

Frederic Laliberté and his colleagues from the University of Toronto wanted to study how climate change will impact how this engine works.

They began by comparing climate records from 1981 to 2012 with climate simulations.

These simulations model how Earth and its atmosphere will change, and cover the period 1982 to 2098.

This comparison revealed that a third of the atmospheric energy is typically involved with the movement of water through the cycle.

But, as a result of climate change, the atmosphere is expected to use more energy during this part of the cycle.

This is because the air will be warmer, so will take up more water, which will create more evaporation and precipitation.

By using more energy to move the water, less energy is used to circulate the air mass, and an increase in water vapour, put simply, will make the process less efficient.

The atmosphere still needs to get rid of the precipitation it collects, but because circulation is affected, it has to do this in fewer, more intense storms.

Air masses that are able to reach the top of the atmosphere are strengthened, while those that can’t, are weakened.

Thunderstorms get  energy from the heat released by the condensation of water vapour (illustrated). Using climate records, and simulations up to 2098, experts said warming will create more precipitation and less circulation. The number of storms will stay the same, but they will become more intense to get rid of the water

Thunderstorms get energy from the heat released by the condensation of water vapour (illustrated). Using climate records, and simulations up to 2098, experts said warming will create more precipitation and less circulation. The number of storms will stay the same, but they will become more intense to get rid of the water

‘We know that with global warming we’ll get more evaporation of the oceans,’ said Mr Laliberte.

‘But circulation in the atmosphere is like a heat engine that requires fuel to do work, just like any combustion engine or a convection engine.’

‘By viewing the atmospheric circulation as a heat engine, we were able to rely on the laws of thermodynamics to analyse how the circulation would change in a simulation of global warming.

‘We used these laws to quantify how the increase in water vapour that would result from global warming would influence the strength of the atmospheric circulation.’

Put simply, Mr Laliberte added ‘powerful storms are strengthened at the expense of weaker storms’, so over the years, atmospheric circulation will adapt to this less efficient form of heat transfer and will cause ‘fewer storms.’ Click HERE to go to the original article.

 

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