Changing jet streams may alter paths of storms and hurricanes

April 16, 2008

The Earth’s jet streams, the high-altitude bands of fast winds that strongly influence the paths of storms and other weather systems, are shifting—possibly in response to global warming. Scientists at the Carnegie Institution determined that over a 23-year span from 1979 to 2001 the jet streams in both hemispheres have risen in altitude and shifted toward the poles.

The jet stream in the northern hemisphere has also weakened. These changes fit the predictions of global warming models and have implications for the frequency and intensity of future storms, including hurricanes.

Cristina Archer and Ken Caldeira of the Carnegie Institution’s Department of Global Ecology tracked changes in the average position and strength of jet streams using records compiled by the European Centre for Medium-Range Weather Forecasts, the National Centers for Environmental Protection, and the National Center for Atmospheric Research. The data included outputs from weather prediction models, conventional observations from weather balloons and surface instruments, and remote observations from satellites. The results are published in the April 18 Geophysical Research Letters.

Jet streams twist and turn in a wide swath that changes from day to day. The poleward shift in their average location discovered by the researchers is small, about 19 kilometers (12 miles) per decade in the northern hemisphere, but if the trend continues the impact could be significant. “The jet streams are the driving factor for weather in half of the globe,” says Archer. “So, as you can imagine, changes in the jets have the potential to affect large populations and major climate systems.”

Storm paths in North America are likely to shift northward as a result of the jet stream changes. Hurricanes, whose development tends to be inhibited by jet streams, may become more powerful and more frequent as the jet streams move away from the sub-tropical zones where hurricanes are born.

The observed changes are consistent with numerous other signals of global warming found in previous studies, such as the widening of the tropical belt, the cooling of the stratosphere, and the poleward shift of storm tracks. This is the first study to use observation-based datasets to examine trends in all the jet stream parameters, however.

Source: Carnegie Institution

Explore further: New Hubble image of the Twin Jet Nebula

Related Stories

New Hubble image of the Twin Jet Nebula

August 26, 2015

The shimmering colours visible in this NASA/ESA Hubble Space Telescope image show off the remarkable complexity of the Twin Jet Nebula. The new image highlights the nebula's shells and its knots of expanding gas in striking ...

Economist discusses turbulent world of aviation reform

August 20, 2015

John Strong knows aviation. For roughly 30 years, the CSX Professor of Finance and Economics at William & Mary's Raymond A. Mason School of Business has immersed himself in the economics, safety and politics of the airline ...

Rosetta's big day in the sun

August 14, 2015

ESA's Rosetta today witnessed Comet 67P/Churyumov–Gerasimenko making its closest approach to the sun. The exact moment of perihelion occurred at 02:03 GMT this morning when the comet came within 186 million km of the sun.

Comet's firework display ahead of perihelion

August 11, 2015

In the approach to perihelion over the past few weeks, Rosetta has been witnessing growing activity from Comet 67P/Churyumov–Gerasimenko, with one dramatic outburst event proving so powerful that it even pushed away the ...

The Planet Saturn

August 3, 2015

The farthest planet from the Sun that be observed with the naked eye, the existence of Saturn has been known for thousands of years. And much like all celestial bodies that can be observed with the aid of instruments – ...

Recommended for you

Earth's mineralogy unique in the cosmos

August 26, 2015

New research from a team led by Carnegie's Robert Hazen predicts that Earth has more than 1,500 undiscovered minerals and that the exact mineral diversity of our planet is unique and could not be duplicated anywhere in the ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.