[Vision2020] "Science" Journal 4-27-12: "Ocean Salinities Reveal Strong Global Water Cycle Intensification During 1950 to 2000"

[Ted Moffett]

Quotes from article at bottom of post about the new peer reviewed
science as described in subject heading:

The warming climate is altering the saltiness of the world's oceans,
and the computer models scientists have been using to measure the
effects are underestimating changes to the global water cycle, a group
of Australian scientists have found.
-------------------------
"The most important part of the research is the basic observation that
the 50-year trend in salinization is indeed that the fresh water is
getting fresher and the saltwater saltier," said Dean Roemmich, a
professor of oceanography at the Scripps Institution of Oceanography.
"It is a fundamental change."
-------------------------
My comments, followed by the "Science" journal abstract on this paper:

In discussions in the general public about anthropogenic climate
change, there is often focus on global air temperatures, the accuracy
of atmospheric temperature data, whether the warming is caused by
natural forcings, whether global atmospheric warming has slowed or
stopped (it hasn't, given a decade by decade comparison, given the
past decade is the warmest since 1880
( http://data.giss.nasa.gov/gistemp/graphs_v3/Fig.A2.gif
http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt ) and
also considering that ironically atmospheric warming is being somewhat
masked by emissions from coal fired plants "Reconciling anthropogenic
climate change with observed temperature 1998–2008"
http://www.pnas.org/content/early/2011/06/27/1102467108

However, the oceans are arguably the most important global factor to
consider when analyzing anthropogenic climate change, given they cover
70 percent of the Earth's surface, are a gigantic heat sink, where
most of the energy from anthropogenic global warming has gone, and
contain critical eco-systems of biological life that both sustain many
human beings and conduct critical functions that maintain the
biosphere, including regulating atmospheric CO2 level and temperature.

The following peer reviewed science is another verification of the
work of climate scientists who have been predicting for decades what
this paper reveals, "global water cycle intensification" with
increased rates of evaporation which can increase both flooding and
drought:

http://www.sciencemag.org/content/336/6080/455.abstract

Science 27 April 2012:
Vol. 336 no. 6080 pp. 455-458
DOI: 10.1126/science.1212222
Report
Ocean Salinities Reveal Strong Global Water Cycle Intensification
During 1950 to 2000
Paul J. Durack1,2,3,4,*, Susan E. Wijffels1,3, Richard J. Matear1,3
+ Author Affiliations

1Centre for Australian Weather and Climate Research, Commonwealth
Scientific and Industrial Research Organisation (CSIRO) Marine and
Atmospheric Research, General Post Office (GPO) Box 1538, Hobart,
Tasmania 7001, Australia.
2Institute for Marine and Antarctic Studies, University of Tasmania,
Private Bag 129, Hobart, Tasmania 7001, Australia.
3Wealth from Oceans National Research Flagship, CSIRO, GPO Box 1538,
Hobart, Tasmania 7001, Australia.
4Program for Climate Model Diagnosis and Intercomparison, Lawrence
Livermore National Laboratory, Mail Code L-103, 7000 East Avenue,
Livermore, CA 94550, USA.
↵*To whom correspondence should be addressed. E-mail: pauldurack at llnl.gov

Abstract

Fundamental thermodynamics and climate models suggest that dry regions
will become drier and wet regions will become wetter in response to
warming. Efforts to detect this long-term response in sparse surface
observations of rainfall and evaporation remain ambiguous. We show
that ocean salinity patterns express an identifiable fingerprint of an
intensifying water cycle. Our 50-year observed global surface salinity
changes, combined with changes from global climate models, present
robust evidence of an intensified global water cycle at a rate of 8 ±
5% per degree of surface warming. This rate is double the response
projected by current-generation climate models and suggests that a
substantial (16 to 24%) intensification of the global water cycle will
occur in a future 2° to 3° warmer world.

Received for publication 4 August 2011.
Accepted for publication 23 March 2012.
-------------------------------------
Wettest Parts of Earth Getting Wetter, Driest Parts Drier

http://www.insidescience.org/news-service/1-2631

Climate-driven changes in ocean salinity over last 50 years could
bring floods and droughts.
Apr 26, 2012

By Joel N. Shurkin, ISNS Contributor
Inside Science News Service

(ISNS) --The warming climate is altering the saltiness of the world's
oceans, and the computer models scientists have been using to measure
the effects are underestimating changes to the global water cycle, a
group of Australian scientists have found.

The water cycle is the worldwide phenomenon of rainwater falling to
the surface, evaporating back into the air and falling again as rain.

The wetter parts of the world are getting wetter and the drier parts
drier. The researchers know this because the saltier parts of the
ocean are getting saltier and the fresher parts, fresher.

Records showed that the saltier parts of the ocean increased salinity
-- or their salt content -- by 4 percent in the 50 years between 1950
and 2000. If the climate warms by an additional 2 or 3 degrees, the
researchers project that the water cycle will turn over more quickly,
intensifying by almost 25 percent.

Reporting in Science magazine, the researchers said the results of the
change in climate would affect agriculture and the ability of drier
areas to capture and use fresh water from rain, creating serious
problems, including droughts and floods. But they had to look offshore
to find their data.

"The oceans are really where the action is happening," said Paul
Durack, the lead author.

The study uses 50 years of data -- from 1950-2000 -- gathered by
instruments, some adrift on the ocean currents, some tethered in
place. Some of the instruments are tiers of bottles that open at
various depths as they are lowered into the sea, and they take
measurements as far down as 9,000 feet.

Durack, who received his Ph.D. from the University of Tasmania, and is
now in a post-doctoral fellowship at Lawrence Livermore Laboratory in
California, said that "salinity shifts in the ocean confirm climate
and the global water cycle have changed."

The oceans cover 71 percent of the Earth's surface. They contain 97
percent of the world's water; receive 80 percent of the rainfall, and
have absorbed 90 percent of the energy produced by global warming.

The relationship between salinity in the sea and the water cycle is
well documented, the scientists wrote. Changes in salinity could also
affect water currents because saltwater is denser than fresh water and
sinks.

Warmer air can absorb more water than cooler air, so as the climate
warms, more water can evaporate into the air. The amount evaporated
increases 7 percent for every degree Celsius the temperature
increases, the scientists reported.

That intensifies the water cycle on both ends of the spectrum. In
places where rainfall exceeds evaporation, the rain is increasing; in
the places where evaporation rates are higher than rainfall, it gets
drier.

Some of the change is directly caused by warmer temperatures. For
instance, the ocean waters around Antarctica are getting less salty
because the waters are being refreshed by the melting ice cap.

Arid areas that require rainfall to provide water for irrigation, for
drinking and industry, will see less rainfall, he said. That is a more
significant threat than just an increase in temperature.

"Changes in the global water cycle and the corresponding
redistribution of rainfall will affect food availability, stability,
access, and utilization," Durack said. "I come from Perth, in dry
western Australia, and you can see the change."

Most computer models depend on land-based observation, which accounts
for the difference, but Durack and his collaborators, Susan E.
Wijffels and Richard J. Matea, think measuring the oceans gives a more
accurate picture, what they called an "identifiable fingerprint."
Their work covers 71 percent of the world's water cycle.

"The most important part of the research is the basic observation that
the 50-year trend in salinization is indeed that the fresh water is
getting fresher and the saltwater saltier," said Dean Roemmich, a
professor of oceanography at the Scripps Institution of Oceanography.
"It is a fundamental change."
--------------------------------------------------------------------------------
Joel Shurkin is a freelance writer based in Baltimore. He is the
author of nine books on science and the history of science, and has
taught science journalism at Stanford University, UC Santa Cruz and
the University of Alaska Fairbanks
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Vision2020 Post: Ted Moffett