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Earth is fighting to stay alive. Mass dieoffs, triggered by anthropogenic assault and fallout of planetary defense systems offsetting the impact, could begin anytime!

Archive for the ‘Ocean Warming’ Category

Earth’s water cycle has accelerated: Researcher

Posted by feww on April 17, 2010

Ocean salinities show an intensified water cycle

Public Release: CSIRO Australia

Evidence that the world’s water cycle has already intensified is contained in new research to be published in the American Journal of Climate.

The stronger water cycle means arid regions have become drier and high rainfall regions wetter as atmospheric temperature increases.

The study, co-authored by CSIRO scientists Paul Durack and Dr Susan Wijffels, shows the surface ocean beneath rainfall-dominated regions has freshened, whereas ocean regions dominated by evaporation are 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.

“This is further confirmation from the global ocean that the Earth’s water cycle has accelerated,” says Mr Durack – a PhD student at the joint CSIRO/University of Tasmania, Quantitative Marine Science program.

“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,” Mr Durack said.

The study finds a clear link between salinity changes at the surface driven by ocean warming and changes in the ocean subsurface which follow the trajectories along which surface water travels into the ocean interior.

The ocean’s average surface temperature has risen around 0.4ºC since 1950. As the near surface atmosphere warms it can evaporate more water from the surface ocean and move it to new regions to release it as rain and snow. Salinity patterns reflect the contrasts between ocean regions where the oceans lose water to the atmosphere and the others where it is re-deposited on the surface as salt-free rainwater.

“Observations of rainfall and evaporation over the oceans in the 20th century are very scarce. These new estimates of ocean salinity changes provide a rigorous benchmark to better validate global climate models and start to narrow the wide uncertainties associated with water cycle changes and oceanic processes both in the past and the future – we can use ocean salinity changes as a rain-gauge,” Mr Durack said.

Based on historical records and data provided by the Argo Program’s world-wide network of ocean profilers – robotic submersible buoys which record and report ocean salinity levels and temperatures to depths of two kilometres – the research was conducted by CSIRO’s Wealth from Oceans Flagship and partially funded by the Australian Climate Change Science Program. Australia’s Integrated Marine Observing System is a significant contributor to the global Argo Program.

Contact: Craig Macaulay
Craig.Macaulay@csiro.au
CSIRO Australia

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Posted in Climate Change, ocean surface, Ocean Warming, water cycle | Tagged: , , , , | Leave a Comment »

Soon All The ‘Paradise’ Would Be Lost!

Posted by feww on July 14, 2009

Image of the Day:

Tikehau Atoll, French Polynesia

tikehau_ali_2009181
The islands and coral atolls of French Polynesia, located in the southern Pacific Ocean … This image from the Advanced Land Imager on NASA’s Earth Observing-1 (EO-1) satellite shows the southern part of Tikehau Atoll, one of the 78 coral atolls that make up the Tuamotu Archipelago. Patches of coral make star-like spots across the turquoise expanse of the lagoon. A line of tree-covered islets encircles the lagoon. At the southernmost tip of the atoll, a large islet accommodates a small village and an air strip. NASA image created by Jesse Allen, using EO-1 ALI data provided courtesy of the NASA EO-1 Team. Caption by Rebecca Lindsey. [Image was reportedly acquired June 30,2009.]

tikehau_ali_2009181_lrg - small
Tikehau Atoll (Full View) magnified image [dated 2005] is available at Google earth  15º 07′ 13 ” S, 148º 13′ 56″ W.

FEWW estimates that human activity emitted about 222 times more CO2 in 2008 than the total sum of  all carbon dioxide spewed from volcanic eruptions that year.

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Posted in French Polynesia, Ocean Warming, rising sea levels, southern Pacific Ocean, Tuamotu Archipelago | Tagged: , , , , | Leave a Comment »

Oceans, Where Life Started, Are Dying – Part II

Posted by feww on March 16, 2008

WILD FACTS SERIES – Lethal Marine Pollution

Major Problems: Fertilizer Runoff; Tourism; Coastal Developments; Marine Transportation; and Ocean Warming due to climate change

Pollution Load

About 80% of the pollution load in the oceans originates from land-based activities directly affecting up to 80 percent of the world’s coastal areas and threatening the well-being of up to 4.5 billion people who live within a 60km radius of the coast, according to the UNEP (about 2billion people live in coastal urban centers).

mega-cities
Of the world’s 23 mega-cities (those with over 2.5 million inhabitants),
16 are in the coastal belt and are growing at a rate of about one million
people per day. ~ UN (Image credit: NOAA)

The sources of water pollution include

  • Municipal and industrial wastes
  • Agricultural runoff
  • Atmospheric deposition


Creeping Dead Zone (Pub. Domain. Credit NASA)

Creeping Dead Zones

The hypoxic (low-oxygen) areas in the oceans are called dead zones. The 200 or so oxygen depleted regions in our oceans are normally caused by nutrients from runoff (chemical fertilizer, manure, sewage…). The increase in nutrients like nitrogen and phosphorous in the water is called eutrophication, a process that promotes excessive growth and decay of weedy plants and that is likely to cause severe reductions in water quality. When the decaying organic matter produced by aquatic vegetation or phytoplankton (an algal bloom) sinks to the bottom it undergoes breakdown by bacteria (bacterial respiration), a process which consumes the dissolved oxygen in the water and produces carbon dioxide. Respiration kills zooplankton, fish, crabs, clams, shrimp, and all other species that swim in the water or dwell on the muddy bottom of the lakes, rivers, estuaries and other water bodies. The water becomes cloudy and turns to a shade of red, yellow, green, or brown.

The size of aquatic and marine dead zones varies from about 1 to 70,000 square kilometers.


A dense bloom of poisonous cyanobacteria in the Potomac River estuary
(Credit:NOAA)

Gulf of Mexico

The largest dead zone in the US coastal waters measures about 25,000 square kilometer in the Gulf of Mexico caused by high-nutrient runoff dumped by the Mississippi River whose vast drainage basin covers the Midwest, the center of U.S. agribusiness. Another dead zone off the coast of Texas was discovered in July 2007.

According to a USGS study most of nutrients (75 percent of nitrogen and phosphorus) come from just nine states (total of 31 states share the basin) in the Mississippi River Basin: Arkansas, Illinois, Indiana, Iowa, Kentucky, Mississippi, Missouri, Ohio, Tennessee. Some 12 percent of the pollution originates from urban sources.

  • Corn and soybean cultivation is responsible for the largest share of nitrogen runoff to the Gulf.
  • Animal manure (see also New Zealand and Australia) on pasture and rangelands contribute a total of 37 percent to phosphors pollution.
  • Crop cultivation is responsible for a total of 43 percent of phosphorus runoff.

Low oxygen levels in the waters of the Gulf Coast have affected the fish reproductive system causing “decreased size of reproductive organs, low egg counts and lack of spawning.” The nation’s largest and most productive fisheries are threatened as the result.

The Following excerpts are from Wikipedia: In a study of the Gulf killifish by the Southeastern Louisiana University done in three bays along the Gulf Coast, fish living in bays where the oxygen levels in the water dropped to 1 to 2 parts per million (ppm) for 3 or more hours per day were found to have smaller reproductive organs. The male gonads were 34% to 50% as large as males of similar size in bays where the oxygen levels were normal (6 to 8 ppm). Females were found to have ovaries that were half as large as those in normal oxygen levels. The number of eggs in females living in hypoxic waters were only one-seventh the number of eggs in fish living in normal oxygen levels. (Landry, et al., 2004)

Another study by the University of Texas at Austin Marine Science Institute was done on the Atlantic croaker fish in Pensacola Bay, Florida. The study was of year-old croakers that live in an estuary that has summer-long hypoxic conditions. During the study, none of the fish spawned at the expected time, or later. Examination of sample fish determined that they lacked mature eggs or sperm. (Murphy, et al., 2004)

Fish raised in laboratory created hypoxic conditions showed extremely low sex-hormone concentrations and increased elevation of activity in two genes triggered by the hypoxia-inductile factor (HIF) protein. Under hypoxic conditions, HIF pairs with another protein, ARNT. The two then bind to DNA in cells, activating genes in those cells.

Under normal oxygen conditions, ARNT combines with estrogen to activate genes. Hypoxic cells in a test tube didn’t react to estrogen placed in the tube. HIF appears to render ARNT unavailable to interact with estrogen, providing a mechanism by which hypoxic conditions alter reproduction in fish. (Johanning, et. al, 2004)

It might be expected that fish would flee this potential suffocation, but they are often quickly rendered unconscious and doomed. Slow moving bottom-dwelling creatures like clams, lobsters and oysters are unable to escape. All colonial animals are extinguished. The normal mineralization and recycling that occurs among benthic life-forms is stifled.

According to USGS Associate Director for Water, Dr. Robert Hirsch, the number of water quality monitoring stations along the Mississippi River Basin region has been decimated from 425 stations 15 years ago to just 32.


A combined sewer overflow runoff entering Fall Creek in Indianapolis, Indiana
(photo credit: Charles Crawford; courtesy USGS).

Agrofuel [biofuel] Crop Impact in The Gulf of Mexico

According to a computer model designed by researchers at the University of Wisconsin-Madison and the University of British Columbia, the exponentially increasing amounts of fertilizer needed to meet US production goals for biofuel production, especially the corn-ethanol, would increase the nitrogen loading from the Mississippi River into the Gulf of Mexico by up to 19 percent, increasing the size of dead zones.

The Mississippi River is about 2,300 miles (3,705 kilometers) long, according to the US Geologic survey. The River Basin or Watershed drains 41% of land in United States, an area of about 1.8 million square miles. Thirty-one states and two Canadian provinces are included in the watershed. The Mississippi carries an average of 500,000 tons of sediment each day.

The US Pacific Coast

Dead zone in the US Pacific coast covers an area of about 3,000 square kilometers. Worsened by strong winds caused by climate change, the Pacific dead zone has reoccurred every summer since 2002. See Photos of research during hypoxic events off the Oregon Coast

ROW

Other countries and regions where other dead zones have been reported since the 1970s include

  • Chesapeake Bay (US)
  • strait called the Kattegat strait (Scandinavia)
  • The Baltic Sea (in multiple fishing grounds)
  • Northern Adriatic
  • And coastal waters of
  • South America
  • China
  • Japan
  • Throughout Southeast Australia
  • New Zealand (Both Australia and NZ are major sources of industrial agriculture as well as sheep and cattle factory farming)


A map of the world’s dead zones created by Dr. Robert Diaz of the Virginia Institute of Marine Science (VIMS). Diaz estimates that the number of dead zones will double within a decade. Source: NASA

Coming Soon:
Oil Pollution

References:

  • Landry, C.A., S. Manning, and A.O. Cheek. 2004. Hypoxia suppresses reproduction in Gulf killifish, Fundulus grandis. e.hormone 2004 conference. Oct. 27-30. New Orleans.
  • Murphy, C. . . . P. Thomas, et al. 2004. Modeling the effects of multiple anthropogenic and environmental stressors on Atlantic croaker populations using nested simulation models and laboratory data. Fourth SETAC World Congress, 25th Annual Meeting in North America. Nov. 14-18. Portland, Ore.
  • Johanning, K., et al. 2004. Assessment of molecular interaction between low oxygen and estrogen in fish cell culture. Fourth SETAC World Congress, 25th Annual Meeting in North America. Nov. 14-18. Portland, Ore.
  • Nutrients in the Nation’s Waters–Too Much of a Good Thing? U.S. Geological Survey Circular 1136.

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See Also:  Our Dying Oceans (Parts I, II,III, and IV)

FEWW Fair Use Notice!

Posted in Climate Change, Coastal Developments, eco tourism, Fertilizer Runoff, Ocean Warming, Tourism, Water pollution | Tagged: , , , | 5 Comments »