Oceans may provide clues to future rainfall

Oct 24, 2008

(PhysOrg.com) -- Changes in the salinity of our oceans are being brought about by man's influence on our climate, suggests new research conducted by the Met Office Hadley Centre and the Walker Institute for Climate System Research at the University of Reading, to be published in Geophysical Research Letters next month.

Using data from the Atlantic Ocean and Met Office climate model simulations, the study reveals increasing salinity in the sub-tropical zone — an indication of less rainfall and increased evaporation. This mirrors decreased rainfall over land areas in the same latitudes identified in previous research in 2007, attributing this to human activity.

Saltiness of the oceans can help us to understand what the likely drying and droughts on land might be in the future. Peter Stott, head of climate monitoring and attribution at the Met Office and leader of the study, explains: "Knowing how our oceans are changing over what are essentially vast data-sparse areas is important. It provides us with a window on changes in the hydrological cycle and gives us more certainty in projections of rainfall as the climate changes. In our region, for instance, this research could help us to refine projections of summer drying extending out from the Mediterranean basin."

Co-author Professor Rowan Sutton of the Walker Institute for Climate System Research at University of Reading said: "The freshening of polar waters in the Atlantic, which has raised fears about a collapse of the warm Gulf Stream current, leading to a significantly colder climate for Europe, looks not to be related to increasing greenhouse gases, but natural variability."

The scientists used a Met Office climate model to simulate variations in the Atlantic Ocean. In the north Atlantic recent freshening, recorded before 2003, has been reversed. These changes could be because of natural variability. However, in the sub-tropics where the increased salinity was found to be outside natural variability, the changes could only be attributed to human-induced global warming.

Provided by University of Reading

Explore further: Magnitude-7.2 earthquake shakes Mexican capital

add to favorites email to friend print save as pdf

Related Stories

Melting during cooling period

11 hours ago

(Phys.org) —A University of Maine research team says stratification of the North Atlantic Ocean contributed to summer warming and glacial melting in Scotland during the period recognized for abrupt cooling ...

Building better soybeans for a hot, dry, hungry world

11 hours ago

(Phys.org) —A new study shows that soybean plants can be redesigned to increase crop yields while requiring less water and helping to offset greenhouse gas warming. The study is the first to demonstrate ...

Researchers decipher climate paradox from the Miocene

Apr 11, 2014

Scientists of the German Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), have deciphered a supposed climate paradox from the Miocene era by means of complex model simulations. ...

UN weather agency warns of 'El Nino' this year

Apr 15, 2014

The UN weather agency Tuesday warned there was a good chance of an "El Nino" climate phenomenon in the Pacific Ocean this year, bringing droughts and heavy rainfall to the rest of the world.

Recommended for you

Magnitude-7.2 earthquake shakes Mexican capital

Apr 18, 2014

A powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets. Some walls cracked and fell, but there were no reports of major damage or casualties.

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

Velanarris
2.3 / 5 (3) Oct 24, 2008
One would think with the rapid melting of ice sheets and glaciers that the sub tropical zones would become less saline. So we're faced with a few logical possibilities:

1) There is no drastic increase in the transport of freshwater into the oceans and ice melt is exaggerated, meaning forecasts of rising oceans, and to a minor extent, most AGW predictions are wrong.

2) There is a great increase in fresh water entering oceans but evaporation of water from the ocean has increased to a greater extent due to gross underestimation of temperature increase, leading to more precipitation, a higher planetary albedo due to cloud cover, and a more homogenous climate around the world. This also means current AGW hypothesis is wrong.

Now those are the extreme cases and in the middle multiple suppositions of the AGW movement have to be wrong, or, the measurements of ocean salinity are wrong.

In any event you're looking at more evidence that counters suppositions of the AGW hypothesis.

Are we ready to stop guessing and start doing science?

More news stories

China says massive area of its soil polluted

A huge area of China's soil covering more than twice the size of Spain is estimated to be polluted, the government said Thursday, announcing findings of a survey previously kept secret.

UN weather agency warns of 'El Nino' this year

The UN weather agency Tuesday warned there was a good chance of an "El Nino" climate phenomenon in the Pacific Ocean this year, bringing droughts and heavy rainfall to the rest of the world.

NASA's space station Robonaut finally getting legs

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...