Global Water Cycle Intensifying

Position of ARGO floats as of 4/16/10, courtesy the University of California San Diego.


A new study (pdf) shows a warming globe is intensifying Earth’s water cycle, making arid regions drier and high rainfall regions wetter. It also finds a clear link between warming-driven salinity changes at the ocean’s surface and changes underwater that match the pathways surface waters take into the deep ocean.

The changes in the water cycle mean that the ocean beneath rainy regions of the globe has freshened, while the ocean in areas dominated by evaporation have grown saltier. The paper also confirms that surface warming of the world’s oceans over the past 50 years has penetrated into the oceans’ interior, changing deep-ocean salinity patterns.

Salinity affects the speed, direction, and depth of ocean currents.

The ocean’s average surface temperature has risen nearly a degree Fahrenheit since 1950.

Lead author Paul Durack at the joint CSIRO/University of Tasmania, Quantitative Marine Science program tells CSIRO:

“This is further confirmation from the global ocean that the Earth’s water cycle has accelerated. These broad-scale patterns of change are qualitatively consistent with simulations reported by the Intergovernmental Panel on Climate Change (IPCC). While such changes in salinity would be expected at the ocean surface—where about 80 per cent of surface water exchange occurs—sub-surface measurements indicate much broader, warming-driven changes are extending into the deep ocean.”

The data for this study come from historical records and from Argo‘s world-wide network of ocean profilers—robotic submersible buoys that record and report ocean salinity levels and temperatures to depths of 1.2 miles.

“Fifty-year trends in global ocean salinities and their relationship to broad-scale warming” is to be published in the American Meteorological Society’s Journal of Climate.
 

DOES IT FEEL LIKE POLITICS IS AT A BREAKING POINT?

Headshot of Editor in Chief of Mother Jones, Clara Jeffery

It sure feels that way to me, and here at Mother Jones, we’ve been thinking a lot about what journalism needs to do differently, and how we can have the biggest impact.

We kept coming back to one word: corruption. Democracy and the rule of law being undermined by those with wealth and power for their own gain. So we're launching an ambitious Mother Jones Corruption Project to do deep, time-intensive reporting on systemic corruption, and asking the MoJo community to help crowdfund it.

We aim to hire, build a team, and give them the time and space needed to understand how we got here and how we might get out. We want to dig into the forces and decisions that have allowed massive conflicts of interest, influence peddling, and win-at-all-costs politics to flourish.

It's unlike anything we've done, and we have seed funding to get started, but we're looking to raise $500,000 from readers by July when we'll be making key budgeting decisions—and the more resources we have by then, the deeper we can dig. If our plan sounds good to you, please help kickstart it with a tax-deductible donation today.

Thanks for reading—whether or not you can pitch in today, or ever, I'm glad you're with us.

Signed by Clara Jeffery

Clara Jeffery, Editor-in-Chief

We Recommend

Latest

Sign up for our newsletters

Subscribe and we'll send Mother Jones straight to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate

Share your feedback: We’re planning to launch a new version of the comments section. Help us test it.