Researchers discover arctic blooms occurring earlier

Scripps oceanography researchers discover arctic blooms occurring earlier
Ice edge blooms often follow retreating ice, as shown here on July 5, 2007, south of Wrangel Island in the eastern Chukchi Sea. Satellite data captured by the NASA MODIS-Aqua sensor, processed by Mati Kahru. Credit: Scripps Institution of Oceanography, UC San Diego

Warming temperatures and melting ice in the Arctic may be behind a progressively earlier bloom of a crucial annual marine event, and the shift could hold consequences for the entire food chain and carbon cycling in the region.

Scientists at Scripps Institution of Oceanography at UC San Diego, along with colleagues in Portugal and Mexico, plotted the yearly spring bloom of phytoplankton—tiny plants at the base of the ocean food chain—in the Arctic Ocean and found the peak timing of the event has been progressing earlier each year for more than a decade. The researchers analyzed satellite data depicting ocean color and phytoplankton production to determine that the spring bloom has come up to 50 days earlier in some areas in that time span.

The earlier Arctic blooms have roughly occurred in areas where ice concentrations have dwindled and created gaps that make early blooms possible, say the researchers, who publish their findings in the March 9 edition of the journal Global Change Biology.

During the one- to two-week spring bloom, which occurs in warm as well as cold regions, a major influx of new organic carbon enters the marine ecosystem through a massive peak in phytoplankton photosynthesis, which converts carbon dioxide into organic matter as part of the global carbon cycle. Phytoplankton blooms stimulate production of zooplankton, microscopic marine animals, which become a food source for fish.

Mati Kahru, lead author of the study and a research oceanographer in the Integrative Oceanography Division at Scripps, said it's not clear if the consumers of phytoplankton are able to match the earlier blooms and avoid disruptions of their critical life-cycle stages such as egg hatching and larvae development.

Scripps oceanography researchers discover arctic blooms occurring earlier
Significant trends toward earlier phytoplankton blooms (blue) were detected in about 11 percent of the area of the Arctic Ocean closest to the North Pole, delayed blooms (red) were evident to the south. Credit: Scripps Institution of Oceanography, UC San Diego

"The spring bloom provides a major source of food for zooplankton, fish and bottom-dwelling animals," he said. "The advancement of the bloom time may have consequences for the Arctic ecosystem."

Such a match or mismatch in timing could explain much of the annual variability of fish stocks in the region.

"The trend towards earlier phytoplankton blooms can expand into other areas of the Ocean and impact the whole ," say the authors, who used satellite data from 1997-2010 to create their bloom maps.

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Mar 02, 2011
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Mar 02, 2011
this is cool

I don't know about that.

But -you're getting warmer!

It is troubling chiefly because a number of migratory species depend upon the food sources arising from these blooms for their survival, and their migrations have been tuned to the cycle prevalent for the past several thousands of years. If that timing is altered significantly over a short enough timespan, it would wreak havoc among those migratory species, as their depended-upon food source might not be available at the critical time when they are present to consume it.

Mar 02, 2011
Looks like an early spring here.

Mar 03, 2011
Oh brother. Again with the old data. That picture was from 2007 (the smallest Arctic minumum on record). Since then, the arctic icesheet has been expanding!

Mar 03, 2011
ubavontuba: Can you please point to the URL or site that shows a monotonic increase in sea ice in the Arctic from 2007 until now? Instead, it is up and down with last year almost as low as 2007 and this winter having less sea ice than 2007. Please take a look at:

I don't know if that will come through well or not so I will also put it in this way (the site has a problem with URLs).


Are you one of the folks who believes that the globe is cooling now? If so, you really need to do some reading.

The arctic ice has been declining for decades. Not monotonically, but in a clearly statistically valid way. Read the article I gave you and watch it over the next few months to see if we have records set. So far it is setting records for each month since December. I don't consider that a long trend but I do find it interesting. Please show me your source showing a monotonic decline.

Mar 03, 2011
Yep, they just released the new ice extent report for Feb. Looks like it might be tied for lowest extent, but they explain that a large part of that is due to circulation of the ice and the location of low pressure systems pulling ice south where it melts, both last year and this year.

The NSIDC record is only a 30 year record though, so "an all-time low" may not be very significant. Time will tell.

Mar 04, 2011

I suspect the ice minimums are most telling.

Here are side by side images of polar minimum from September 19, 2007 and 2010:


It's quite apparent the sea ice minimum from this past season is substanatially greater. In fact every year since 2007 is obviously greater.

You can enter all sorts of dates. But sadly, winter 2004/2005 data is unavailable.

It is apparent the sea ice is substantially reduced from earlier decades though.

It's also interesting to study the increasing maximum winter snow cap.

And here's a graph of the Antarctic sea ice which indicates it's generally been trending above the mean for the past two years (but it's dipped a little recently):


Anyway, it's too early to say the recent sea ice advances indicate a long term trend, but it is a hopeful sign.

Apr 01, 2011
Global Cooling is occurring since the blooms are earlier. This phenomenon has nothing to do with CO2 concentrations but the recovery of the plankton populations after decades of atomic weapon testing. if there are no further tests or oil spills than the fish stocks will also recover. It is obvious that if you destroy the phytoplankton by bombing than the bacteria will take over and suppress the phytoplankton. It takes a long time to recover. if it had not happened the ocean would die and we would go back to precambrian times with little Oxygen to breathe and water would also evaporate leaving a Martian landscape.

Apr 01, 2011
Wow, 13 years of data.
"The advancement of the bloom time may have consequences for the Arctic ecosystem."
Do you think?

Apr 02, 2011
Oh Boy.

Significant trends toward earlier phytoplankton blooms (blue) were detected in about 11 percent of the area of the Arctic Ocean closest to the North Pole, delayed blooms (red) were evident to the south. Credit: Scripps Institution of Oceanography, UC San Diego

It's just another report of a trend where AGW warming is effecting the global ecosystem. Come on ryygesogn2, think of the poor algae having to live longer because arctic winters are shorter and the water is warmer. It's a good thing right?

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