The effect of global warming on rain in general is well known: As carbon dioxide and other greenhouse gases entering the atmosphere, their presence increases the temperature, which in turn leads to increase in the amount of water vapor in the atmosphere. When developing storm systems, the higher humidity promotes greater precipitation, so that higher temperatures contributes to the rain becoming more extreme.
For years, the scientific community has been developing models and simulations of Earth’s climate that can be used to help understand the effect of global warming on extreme rain from around the world. Many of the existing models do a decent job of simulating rainfall for areas outside of the tropics.
However, with regard to precipitation in the tropics, these models do not fit together. The reason can be reduced to its resolution: Climate models simulate weather systems dividing the globe into a grid, with each square of the grid represents a large plot of land or sea. The large weather systems that occupy more than one box, like those often act in Europe or the United States in winter, are relatively easy to simulate. Instead, smaller storms range, and more isolated as occur in the tropics can be more difficult to take into account.
All indications are that global warming will intensify extreme precipitation in the tropics, but, so far, has not been at all clear how fast it will.
A new study may provide critical data to help clarify the issue. The study has yielded estimates of enhanced tropical rainfall extremes. These estimates are based on the observations and simulations on some models.
The team of Paul O’Gorman, Professor of Atmospheric Sciences at the Massachusetts Institute of Technology (MIT) in Cambridge, U.S., has concluded that with each degree Celsius rise in temperature, the tropical regions will experience events extreme precipitation 10 percent stronger, with consequences such as flooding in populated areas.
The study found that, compared to what happens in other regions of the world, extreme precipitation in the tropics respond differently to climate change. There appears to be more sensitive to global warming. There will have need to investigate further to determine the exact causes of this.