Scientists Study Eyes of
Hurricanes to Predict Their Intensity
There have been many improvements in how weather experts predict the
path of hurricanes, powerful storms that form in the ocean.
However, forecasters still struggle when trying to estimate one quality
of a coming storm: its intensity.
Intensity measurements would help people prepare for flooding and deadly
winds, like those of Hurricane Maria last year. Maria killed an
estimated 4,465 people, severely damaged the electrical power system and
caused $90 billion in damage in Puerto Rico.
Steve Bowen is the director and weather expert for the insurance company
Aon Benfield’s Impact Forecasting team. He said it is helpful to know
where a hurricane is going, but more information about its intensity is
needed.
“We sort of have half the circle filled in, and we need to get that
other half filled in,” Bowen told the Reuters news service.
Some climate scientists have said that warming sea and air temperatures
have added more energy to the storms. And this might affect intensity
predictions.
Kerry Emanuel is a climate professor at the Massachusetts Institute of
Technology. In a recent academic paper, he wrote: “Climate change
potentially affects the frequency, intensity and tracks of” hurricanes
and other similar storms.
In 2017, the U.S. government’s National Hurricane Center reported that
it had failed to correctly predict the sudden intensification of the
2016 hurricane called Matthew. That storm strengthened very quickly,
with winds reaching up to 270 kilometers per hour. It caused major
destruction in the Caribbean, including killing more than 1,000 people
in Haiti, according to Reuters.
Scientists say there are several scientific models for predicting
hurricane intensity, but they are all of limited use.
The current science of tracking a storm’s path depends heavily on
information about conditions on its edges. But, intensity is based on
what is happening in the middle of it.
Generally, measurements are taken one of three ways. Sometimes
researchers fly a ‘hurricane hunter’ aircraft into the storm. Other
times, they use a device called a weather buoy to measure wind speeds as
a storm passes over. Or, they get information from satellites.
One project to gather more information to predict intensity is the
Cyclone Global Navigation Satellite System, or CYGNSS for short. CYGNSS
is a group of eight low-orbit satellites. The American space agency,
NASA launched it in 2016.
Earlier satellites had trouble measuring ocean surface winds at the
center of storms. Heavy rain at the center often weakened their signals,
NASA officials said.
Christopher Ruf is a lead investigator with CYGNSS and a climate science
professor at the University of Michigan. He noted, “For storms that are
changing really quickly, you could miss something like rapid
intensification.”
NASA designed CYGNSS to measure surface winds in and near the center of
tropical storm systems. Researchers said that having more satellites
means they can pass over the storms more often. And the low-orbit
satellites are closer to the storms. So, experts get more real-time
information to use for predicting intensity.
At present, researchers are focusing on the 2017 season when hurricanes
severely affected Texas, Florida and Puerto Rico. Storms caused hundreds
of billions of dollars in damage. And researchers are re-examining
information gathered from CYGNSS to see how it affected the quality of
the forecasts and how it can be better used to predict intensity.
CYGNSS could be fully operational next year, researchers said. |