The accuracy of weather forecasts affects much of our daily lives. Knowing whether it will rain helps you plan accordingly: clothes, transportation, and in the case of a storm, safety.
Meteorologists consider observations at a given time and, based on their models, make predictions every six hours for two weeks. And if the prediction was off — “a forecast bust, as they say,” explains geophysical sciences Prof. Tiffany Shaw — meteorologists can figure out what went wrong and improve the model accordingly.
Climate forecasts work in much the same way, except it can take years — even decades — to find out if a projection was a bust. For more than 40 years, physical climate scientists like Shaw have been predicting how the global climate has changed in the historical period and how it might change into the 21st century under different emission scenarios.
Now we are really coming into a time where the predicted signals are beginning to emerge in observations and scientists can ask: Are those changes consistent with what we predicted? And if not, is there a problem with our models or are we simply seeing natural variations in climate?
Shaw hopes to answer these questions as part of a new project in collaboration with the National Oceanic and Atmospheric Administration.
Seasonal storm strength
Shaw’s past work has focused on the “harbingers of the future” due to the burning of fossil fuels, with extensive research on the response of the atmosphere to anthropogenic climate change, including the response of midlatitude weather systems (highs and lows) that form the so-called storm track. In particular, both theory and generations of climate models have predicted that in the southern hemisphere, storms should get stronger throughout the winter; winds or temperature fluctuations should increase, and precipitation should become more extreme.
“In the northern hemisphere, our models predict that storms should get weaker in summer, even though they already are weaker to begin with.”