Thermometer in the earth

A new look at historical ocean temperatures confirms what climate models have already said: The ocean – and therefore the world – is heating up.

Abraham: “Turns out 93 percent of the global warming heat goes into the ocean. So if you really want to know global warming, you’ve really got to measure ocean warming.”

That’s John Abraham of the University of Saint Thomas in Minnesota. He says a high-tech and extensive system of buoys has been used to collect ocean temperature data for the past 17 years.

But sailors have been recording water temperatures in more low-tech ways since the 1940s.

Abraham: “The first serious measurements of the oceans were through buckets sent by scientists over sides of ships.”

But this historical data was incomplete. For example, temperature readings from the shipping lanes between Europe and North America were common, while very few existed for the southern oceans.

So Abraham and his team used a technique called “mapping” to fill in the missing pieces. Then they compared their findings to computer climate model simulations.

Abraham: “And we found out that they were almost in perfect agreement.”

Abraham says his study adds to the pile of evidence showing that the world’s oceans are heating up.

Reporting credit: Mark Knapp/ChavoBart Digital Media.
Image graphic: Created by David McCarthy.

Bruce Lieberman, a long-time journalist, has covered climate change science, policy, and politics for nearly two decades. A newspaper reporter for 20 years, Bruce worked for The San Diego Union-Tribune...