Study: Some Areas Cooling Despite Global Warming

By Michael Bastasch

New research out of Florida State University (FSU) claims that the world has been warming over the past 100 years, but that warming trend hasn’t affected all areas of the globe equally.  [contextly_auto_sidebar id=”055uQndmwOgV9vhgeH17zxV9ss90Fniq”]

“Global warming was not as understood as we thought,” said Zhaohua Wu, assistant professor of meteorology at FSU, who led the research team.

While some areas have warmed others have actually cooled, researchers found. Wu’s team analyzed global land and surface temperature trends since 1900 and found that warming first started around both the arctic and subtropical regions in both hemispheres — though researchers did not look at temperatures from Antarctica.

The largest amount of warming occurred in northern hemisphere mid-latitude regions, but some areas of the world, including the some equatorial regions, were actually cooling down. Leading the team to say that the regional cooling is still part of an overall warming trend.

“The global warming is not uniform,” said Eric Chassignet, director of FSU’s Center for Ocean-Atmospheric Prediction Studies. “You have areas that have cooled and areas that have warmed.”

Researchers said that data from 1910 to 1980 show that equatorial areas near the Andes mountains in South America were actually cooling. Temperatures in those areas stabilized until the mid 1990s when they started to warm. In other parts of the world, temperatures haven’t significantly changed at all.

The groups research is published in the journal Nature Climate Change. While the study still argues that cooling areas are dwarfed by an overall warming trend, it still shows that initial assumptions that the global warming will affect all areas of the global at the same time.

“The global climate has been experiencing significant warming at an unprecedented pace in the past century,” the FSU study says. “This warming is spatially and temporally non-uniform, and one needs to understand its evolution to better evaluate its potential societal and economic impact.”

“We find that the noticeable warming (>0.5 K) started sporadically over the global land and accelerated until around 1980,” the study continues. “Both the warming rate and spatial structure have changed little since. The fastest warming in recent decades (>0.4 K per decade) occurred in northern mid-latitudes. From a zonal average perspective, noticeable warming (>0.2 K since 1900) first took place in the subtropical and subpolar regions of the Northern Hemisphere, followed by subtropical warming in the Southern Hemisphere.”

While the study warns of accelerated warming in the 20th century, there has been no warming since the late 1990s — about 17 years and 9 months.

In fact, some scientists have been arguing that the last warming trend was indicative of increasing solar activity and ocean oscillation cycles. Now solar activity is declining, which could cause the world to cool in the years to come.


“Attention in the public debate seems to be moving away from the 15-17 year ‘pause’ to the cooling since 2002,” writes Dr. Judith Curry, the chair of the School of Earth and Atmospheric Sciences at Georgia Institute of Technology.

Curry says the period since 2002 ss “scientifically interesting” as “it coincides with the ‘climate shift’” of roughly 2001-02. “This shift and the subsequent slight cooling trend provides a rationale for inferring a slight cooling trend over the next decade or so, rather than a flat trend from the 15 [year] ‘pause’,” she said.

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