Sea life's importance to the climate
Does the marine biosphere mix the ocean? A group of oceanographers led by W.K. Dewar of Florida State University argue that the swimming action of fish and other marine organisms may play a critical role in driving ocean currents. If true, large-scale over-fishing or the collapse of the marine food chain due to pollution or ocean acidification may cause significant changes in ocean currents--and Earth's climate.
Figure 1. Rainbow made From a sperm whale using his blowhole. Image taken June 17, 2006 in Kaikora, New Zealand by wunderphotographer jhfelder.
The Meridional Overturning Circulation (MOC) or Thermohaline Circulation is a well-known feature of the ocean circulation. In the Atlantic, the Gulf Stream current forms a portion of the MOC. Gulf Stream waters flow to the region near Greenland, where an input of fresh, denser water from melting ice and river run-off creates a downward flow of water that then moves southward along the ocean bottom towards the Equator. This deep water eventually returns to the surface in the mid-Atlantic to complete a cell of the MOC. Scientists have long thought that the energy needed to drive the MOC came from winds and tides--about two terrawatts of energy (Munk and Wunsch, 1998). However, Dewar et al. show that the mechanical energy added to the ocean by the swimming action of whales is about 1% of this total, and the swimming action of other marine organisms (primarily zooplankton) adds up to 50% of this total--one terrawatt of energy. While the authors admit that their calculations may have large errors, this research shows that marine life may have a heretofore unappreciated large impact on Earth's climate. Our climate is intimately connected to the sun, life on land, life in the ocean, and human activities in an incredibly complex web of interconnections. It is our challenge to understand this system, even as we change it and it changes of its own accord.
My next blog will be Thursday afternoon, when the new Dr. Bill Gray/Phil Klotzbach Atlantic hurricane season forecast will be released.
Jeff Masters
Dewar, W.K., R.J. Bingham, R.L. Iverson, D.P. Nowacek, L.C. St. Laurent, and P.H. Wiebe, 2006, "Does the marine biosphere mix the ocean?", Journal of Marine Research, 64, 541-561.
Munk, W., and C. Wunsch, 1998, "Abyssal recipes II: Energetics of tidal and wind mixing", Deep-Sea Res., 45, 1976-2009.
Reader Comments
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kind of early but the rain woke me up
Very impressive blow up to our wsw
Pressure on my weather station is 1009.7 and steady.Winds calm now out of the ene@4
Could get real interesting today.
Motion looks to be to the E or ESE
only 4:20 here
will post update on local conditions in 3 hrs or so
Wind Speed (WSPD): 21.4 kts
Wind Gust (GST): 23.3 kts
Wave Height (WVHT): 6.6 ft
Dominant Wave Period (DPD): 6 sec
Average Period (APD): 4.8 sec
Mean Wave Direction (MWD): E ( 93 deg true )
Atmospheric Pressure (PRES): 29.77 in
Pressure Tendency (PTDY): -0.07 in ( Falling )
Air Temperature (ATMP): 79.5 F
Water Temperature (WTMP): 83.7 F
Dew Point (DEWP): 75.0 F
Heat Index (HEAT): 83.8 F
05 30 1550 NE 13.6 15.5 3.0 6 4.8 E 29.90 +0.02 80.2 83.8 75.9 - - -
05 30 1450 ENE 11.7 13.6 3.0 7 4.7 E 29.90 +0.04 80.4 83.8 76.8 - - -
05 30 1350 NE 1.9 3.9 3.3 5 4.8 E 29.88 +0.04 79.0 83.7 75.6 - - -
05 30 1250 SSE 9.7 19.4 3.3 5 4.7 ENE 29.88 +0.04 76.6 83.8 73.6 - - -
05 30 1150 ESE 7.8 9.7 3.6 7 4.9 E 29.85 +0.02 82.4 83.8 76.5 - - -
05 30 1050 ESE 11.7 13.6 3.9 7 5.0 E 29.84 +0.00 82.2 83.8 76.6 - - -
05 30 0950 ESE 11.7 13.6 4.3 7 5.0 E 29.84 +0.00 81.9 83.8 75.9 - - -
05 30 0850 ESE 9.7 13.6 4.6 7 5.0 ENE 29.83 -0.04 81.0 84.0 77.2
I see that there is a nice blob of convection where this low should be developing. Wonder if we will get the L on the surface map today? You can find a large detailed surface map from here.
The CMC has been locked on to the same track for quite a while now and it looks like the GFS has shifted a little N with this feature.
Got to get to work. Y'all have a great day.
GOM VIS
Link 2
"The Caribbean Sea...
all the numerous strong showers and thunderstorms in the eastern
Pacific Ocean...from 10n to 15n between Central America and
94w...are not related to Tropical Storm Barbara. This rain in
the eastern Pacific Ocean is related to a middle to upper level
cyclonic circulation center over interior sections of Central
America. A 1006 mb surface low pressure center developed at
31/0900 UTC near 19n87w near the Banco chinchorro...just east
of the Yucatan Peninsula. A trough GOES from the low center
to El Salvador near 13n88w. Numerous strong showers and
thunderstorms are from 16n to 21n between 80w and 86w."
Viewing: 1101 - 1151
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