Plankton Cool Off With Own Clouds

Status
Not open for further replies.
Z

zavvy

Guest
<b>Plankton Cool Off With Own Clouds </b><br /><br />Phytoplankton may be small, but that doesn't mean they can't do big things -- like change the weather to suit their needs. <br /><br />A recent study funded by NASA's Earth Science Department shows that the tiny sea plants release high quantities of cloud-forming compounds on days when the sun's harmful ultraviolet rays are especially strong. The compounds evaporate into the air through a series of chemical processes that result in especially reflective clouds. This, in turn, blocks the radiation from bothering the phytoplankton.<br /><br />The findings not only confirm earlier theories that plankton are linked to the creation of clouds above the ocean but could also lead to a better understanding of how living things affect the Earth's climate. <br /><br />"The take-home message is that all the processes that are going on in the ocean and the climate are very tightly connected," said David Siegel, co-author of the study and director of the Institute for Computational Earth System Science in Santa Barbara, California. "This is really the impetus for other researchers to look into the whole cycle of how biology and climate interact." <br /><br />Siegel and Woods Hole Oceanographic Institution researcher Dierdre Toole announced the results of their study in the May issue of the Geophysical Research Letters, a scientific journal. <br /><br />The two researchers performed the study on measurements taken off the coast of Bermuda. There, they found that the ocean levels of a compound called dimethylsulfoniopropionate, or DMSP, were directly related to the level of ultraviolet radiation reaching the phytoplankton that live near the ocean's surface. <br /><br />DMSP is an important link in the plankton-to-cloud cycle because, as it leaves the phytoplankton cells and enters into the water, bacteria break it down into a chemical called dimethylsulfide, or DMS. Evaporated water, in turn, carries the DMS into the air where the chemical rea
 
E

earthseed

Guest
Thanks for the interesting article, zavvy. This, of course, is evidence for the Gaia Hypothesis, which claims that biology regulates the Earth's climate. My only problem with this idea is that much of the climate regulation is done by geology.<br /><br />My question is how would plankton evolve this capability? James Lovelock, the originator of Gaia, conjured up a "Daisy World", a planet with only one life form - daisies that be either dark or light coloured. A cool climate would favor dark daisies because they retain heat, while a warm climate would favor light reflecting daisies. This works in terms of evolution because the daisies would create a micro-climate around themselves that would provide the necessary feedback for natural selection.<br /><br />The phytoplankton effect described here must operate on a much larger scale. So there is no way to select individuals that produce the cloud-forming compounds, because their non-producing neighbors benefit equally. This implies that the selection must be happening on a large group basis, which is not the conventional view of evolution.
 
Z

zavvy

Guest
<font color="yellow">My question is how would plankton evolve this capability?</font><br /><br />I wish I had a clue. The story amazed me when I read it!<br /><br />It sort of reminded me of this BBC article I read about Hippos and their ability to secrete sunscreen...<br /><br />It also makes me wonder what we humans might be doing subconsciously that could affect our planet's future ... <img src="/images/icons/smile.gif" /><br /><br />
 
Status
Not open for further replies.

Latest posts