June 11, 2012
ICESCAPE scientist Karen Frey taking optical measurements in a melt pond, with the U.S. Coast Guard Cutter Healy on the background. Photo: NASA's Goddard Space Flight Center/Kathryn Hansen.
"This is like finding the Amazon rainforest in the middle of the Mojave Desert," said Paula Bontempi, NASA's ocean biology and biogeochemistry program manager, in a press release. "We embarked on ICESCAPE to validate our satellite ocean-observing data in an area of the Earth that is very difficult to get to. We wound up making a discovery that hopefully will help researchers and resource managers better understand the Arctic."
The researchers hypothesize that the plankton are thriving off sunlight magnified through pools of water atop ice sea. As sea ice melts, water collects on the top of the pack, focusing sunlight into nutrient-rich waters just below the ice and creating an explosion of life. Prior to this, researchers had assumed that the sea ice would have blocked any sunlight, making it impossible for plankton to thrive.
The under-ice plankton bloom also turned out to be particularly fecund. They doubled in number more than once a day, while plankton in open Arctic waters only double every two to three days.
"At this point we don't know whether these rich phytoplankton blooms have been happening in the Arctic for a long time and we just haven't observed them before," said Kevin Arrigo leader of the ICESCAPE mission and lead author of a new study describing the phenomenon in Science. "These blooms could become more widespread in the future, however, if the Arctic sea ice cover continues to thin."
Climate change due to anthropogenic greenhouse gas emissions is warming the Arctic faster than anywhere else on Earth. One of the impacts has been a decline in old ice--which doesn't melt seasonally--and an increase in younger and thinner ice, which may be facilitating these below ice plankton blooms.
Plankton play an important role in sequestering carbon dioxide, so if the blooms are common it could provide new insight into how much carbon Arctic ecosystems are soaking up.
When light reaches the nutrient-rich waters under the Arctic ice cap, it creates the perfect environment for phytoplankton to bloom. Credit: Don Perovich/U.S. Army Cold Regions and Engineering Laboratory.
Climate change has rapidly shrunk Arctic sea ice over the past thirty-plus years. Images showing the Arctic sea ice minimum in September of 1979 (the year satellites started recording sea ice extent) and in September of 2011. Credit: NASA.
Climate change creating "novel ecosystem" in Arctic
(06/06/2012) If melting sea ice and glaciers weren't enough, now climate change is producing what researchers call a "structurally novel ecosystem" in the northwestern Eurasian tundra. Warmer weather and precipitation changes in the region, which covers western Russia into Finland, has allowed shrubs of willow and alder to grow into sparse forests within just forty years, according to a new study in Nature Climate Change. The new ecosystem could have global implications as researchers say it is likely to worsen global warming due to a decline in the region's albedo, i.e. the sunlight reflected back into the atmosphere due to snow cover.
Just how far can a polar bear swim?
(05/03/2012) Polar bears (Ursus maritimus) are capable of swimming incredible distances, according to a new study published in Zoology, which recorded polar bears regularly swimming over 30 miles (48 kilometers) and, in one case, as far as 220 miles (354 kilometers). The researchers believe the ability of polar bears to tackle such long-distance swims may help them survive as seasonal sea ice vanishes due to climate change.
Obama Administration, Shell moving ahead with Arctic oil exploitation
(04/02/2012) Last week, the U.S. Department of the Interior approved oil spill clean-up plans by Royal Dutch Shell Oil in the Beaufort Sea, paving the way for offshore oil drilling in the Arctic to begin as soon this year. The Interior's approval was blasted by environmentalists, who contend that oil companies have no viable way of dealing with a spill in the icy, hazardous conditions of the Arctic, far from large-scale infrastructure. Shell, which has spent $4 billion to date to gain access to the Arctic, must still be granted final permits for drilling.
Arctic warms to highest level yet as researchers fear tipping points
(02/13/2012) Last year the Arctic, which is warming faster than anywhere else on Earth due to global climate change, experienced its warmest twelve months yet. According to recent data by NASA, average Arctic temperatures in 2011 were 2.28 degrees Celsius (4.1 degrees Fahrenheit) above those recorded from 1951-1980. As the Arctic warms, imperiling its biodiversity and indigenous people, researchers are increasingly concerned that the region will hit climatic tipping points that could severely impact the rest of the world. A recent commentary in Nature Climate Change highlighted a number of tipping points that keep scientists awake at night.
Opposition rising against U.S. Arctic drilling
(02/09/2012) Drilling in the Arctic waters of the U.S. may become as contested an issue as the Keystone Pipeline XL in up-coming months. Scientists, congress members, and ordinary Americans have all come out in large numbers against the Obama Administration's leases for exploratory drilling in the Beaufort Sea and the Chuckchi Sea.