CONSENSUS: Still No Connection Between Global Warming And Floods

REUTERS/Richard Carson

Daily Caller News Foundation logo
Michael Bastasch Contributor
Font Size:

As scientists and media pundits debate human activity’s role in Hurricane Harvey, a new study finds no evidence global warming increased flooding over North America and Europe.

A study published in the Journal of Hydrology found “the number of significant trends in major-flood occurrence across North America and Europe was approximately the number expected due to chance alone.”

In fact, the study only adds to the Intergovernmental Panel on Climate Change’s (IPCC) 2013 findings that there’s little to no evidence of increased flooding across the world amid rising temperatures. IPCC findings are regarded as scientific “consensus” by most  climate scientists.

“The results of this study, for North America and Europe, provide a firmer foundation and support the conclusion of the IPCC that compelling evidence for increased flooding at a global scale is lacking,” reads the study by an international team of scientists.

The team, led by U.S. Geological Survey scientist Glenn Hodgkins, examined data from hundreds of flood gauges, looking at periods from 1931 to 2010. What they found was flooding was more correlated with decadal natural ocean cycles than long-term global climate change.

“Generalizations about climate-driven changes in floods across large domains or diverse catchment types that are based upon small samples of catchments or short periods of record are ungrounded,” the study found.

The study’s findings support data from the Environmental Protection Agency (EPA). About 60 percent of locations where the EPA measures flooding show a decrease in “magnitude and intensity since 1965,” according to University of Colorado professor Roger Pielke Jr.

Pielke also found that flood damage has been declining as a proportion of the U.S. economy since 1940 — that way you control for population growth and development.

Scientists predict man-made warming from greenhouse gas emissions will increase the frequency and severity of extreme weather events, like rainfall and storms. That, in turn, could increase flooding.

In the wake of Hurricane Harvey, scientists and media pundits have debated the storm’s connection to global warming. Climate scientist Michael Mann argued that while human activity didn’t “cause” the storm, sea level rise and higher ocean temperature made it more severe.

Harvey made landfall as a Category 4 hurricane Friday night. Rescuers have evacuated thousands of people from flooded homes, and at least 20 people have died.

A New York Times editor urged readers to ignore science and realize global warming played a role in Harvey’s destructiveness.

The IPCC has found no significant upward trend in hurricanes, and National Oceanic and Atmospheric Administration scientists warned it was “premature to conclude that human activities … have already had a detectable impact on Atlantic hurricane or global tropical cyclone activity.”

Whatever the validity of Mann’s argument, the Houston area experienced record levels or rainfall and thousands of residents had to flee their homes as the flood waters closed in. southeastern Texas and southern Louisiana have gotten about 25 trillion gallons of rain.

New Orleans officials worried they would be inundated with flooding for the second time in as many weeks after a water pump broke as Harvey turned north. The city was spared the worst of Harvey’s rains, however, and there hasn’t been much flooding.

Follow Michael on Facebook and Twitter

Content created by The Daily Caller News Foundation is available without charge to any eligible news publisher that can provide a large audience. For licensing opportunities of our original content, please contact