Warming and the Oceans
The world, and the ocean, is getting warmer. Average global
temperatures are on the rise and increasing temperatures
at the Earth's surface are accompanied by a significant
rise in ocean temperatures to a depth of several hundred meters. Why
is the Earth getting warmer? How will this affect the oceans?
Many already know this story, but it is worth review.
The burning of fossil fuels to drive cars, power factories, generate electricity and other "necessities" of modern life produces global warming pollutants. This
creates "greenhouse gases", trapping heat in the
atmosphere and in the oceans. The result of this,
the greenhouse effect, has caused the Earth to heat
up by about one degree Fahrenheit over the past
century, with the most intense warming occurring
over the last two decades. to learn what the Joint Ocean Commission Initative says about the oceans and climate change.
What's at Stake
Our ocean covers about three-fourths of the Earth
and by storing a thousand times more heat than the
atmosphere does, it plays a key role in regulating
the global climate. To learn more about what global
warming is doing to the health of our oceans, read
the section below: "The Potential Effects of Global
Warming on our Oceans"
Potential Effects of Global Warming on our Oceans
Sea Level Rise
Many experts warn that global warming will cause sea levels
to rise dramatically. The rise in sea levels is due to two
Thermal Expansion: Warmer water takes up more room than
cooler water, which causes sea levels to rise.
Melting Ice: Glaciers and sea ice in both the Northern
and Southern Hemispheres continue melting at rapid rates.
As land-bound ice melts and flows into the ocean, sea
Rising sea levels may completely submerge low-lying island
nations and will certainly have devastating impacts on coastal
populations worldwide. To learn more about the global effects
of rising sea levels, click on the links below:
Herald Tribune: Climate change to cause droughts, sea level
rise in Australasia, research shows
The Iceflow Cometh
Disruption of the Global Ocean Conveyer
As glaciers and
ice-sheets melt from rising global temperatures, they release
fresh water which interferes with the formation of dense
"bottom water". That "dense" water sinks to the ocean floor
and helps drive the global ocean conveyor belt. The slowing
(or halt) of the global ocean conveyor belt due to global
warming would have disastrous effects on the way the ocean
distributes heat around the world. To learn more about the
effects of a disrupted global ocean conveyor belt, click
on the links below:
Conveyor Belt of Heat
A conceptual model of global ocean circulation.
Chemical Changes - Ocean Acidification
"Warming of the Southern Ocean Since the 1950s", Science Magazine, http://www.sciencemag.org/cgi/content/abstract/295/5558/1275, February 2002.
"Climate Change 101: Understanding and Responding to Global Climate Change", Pew Center on Global Climate Change, http://www.pewclimate.org/global-warming-basics/climate_change_101/.
Water Encyclopedia, Science and Issues: Ocean Basins, Section Mi-Oc. http://www.waterencyclopedia.com/Mi-Oc/Ocean-Basins.html
"Ice sheet complexity leaves sea level rise uncertain", NewScientist.com news service, http://www.newscientist.com/article/dn11396-ice-sheet-complexity-leaves-sea-level-rise-uncertain.html, March 2007.
United Nations Environment Program, Potential impacts of climate change, 30. Great ocean conveyor belt. http://www.grida.no/climate/vital/32.htm.