A new study has found that humidity is more important than heat when it comes to measuring global heating.
Researchers claim that temperature is not enough to determine climate change’s effects on the tropics. Researchers say that temperature alone is not a good way to measure climate change’s weird weather and downplays impacts in the tropics. However, they found that adding heat and air moisture to the equation makes it nearly twice as bad.
Extreme weather events like storms, floods, and rain are influenced by the amount of water in air. A team of scientists from the U.S., China and India decided to use an obscure measurement of weather called equivalent potential temperature or “theta-e” that reflects “the moist energy of the atmosphere.” V. Ramanathan (climate scientist at Cornell University and Scripps Institution of Oceanography) was co-author of the study. It is expressed in degrees like temperature.
Ramanathan stated that there are two main drivers of climate change: humidity and temperature. “And we have so far only measured global warming in terms of temperature.”
He said that by adding energy from humidity, the extremes (heat waves, rain, and other extremes) correlate better.
This is because the air retains more moisture as the world heats. It’s nearly 4% for each degree Fahrenheit and 7% for each degree Celsius. Ramanathan stated that when moisture condenses, it releases heat and energy.
He also said that water vapor in the atmosphere is a powerful heat-trapping gas, which can increase climate change.
The world has experienced a temperature rise of 1.42 degrees (0.79 Celsius) between 1980 and 2019. The study found that the world has warmed up and moistened by 2.66 degrees (1.48 Celsius) since 1980, when energy from humidity is taken into account. The warming in the tropics was even greater at 7.2 degrees (4° Celsius).
Ramanathan stated that if you only look at temperature, it seems like warming is more pronounced in North America and the mid-latitudes, and especially the poles. It’s also less noticeable in the tropics.
He said that this is not true because of the high humidity in tropical tropics, which boosts storm activity from regular storms and tropical cyclones to monsoons.
Ramanathan stated that this increase in latent energy in the air leads to extreme weather conditions: flooding, storms, and droughts.
Donald Wuebbles from the University of Illinois, a climate scientist, said that it made sense, as water vapor is crucial in extreme rains. Wuebbles stated that both heat and humidity are crucial.
Katharine Mach, an environmental scientist at the University of Miami, was not part of the study. She said that “humidity plays a key role in shaping the effects of heat on human health, well-being, and the future.”