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There are several interesting climate related studies in this week's Science magazine.
Greenland Ice Slipping Away but Not All That Quickly
Almost 6 years ago, a paper in Science warned of an unheralded
environmental peril. Melted snow and ice seemed to be reaching the base
of the great Greenland ice sheet, lubricating it and accelerating the
sheet’s slide toward oblivion in the sea, where it was raising sea
level worldwide (12 July 2002, p. 218).
A new study has confirmed that meltwater reaches the ice sheet’s
base and does indeed speed the ice’s seaward flow. The good news is
that the process is more leisurely than many climate scientists had
feared. Glaciologist Richard Alley of Pennsylvania State University in
State College says, "It matters, but it’s not huge.” The finding should
ease concerns that Greenland ice could raise sea level a disastrous
meter or more by the end of the century.
Read more at PHYSORG.com: Lakes of meltwater can crack Greenland's ice and contribute to faster ice sheet flow
Coral Adaptation in the Face of Climate Change
IN THEIR REVIEW, “CORAL REEFS UNDER RAPID CLIMATE CHANGE and ocean
acidification” (14 December 2007, p. 1737), O. Hoegh- Guldberg et al.
present future reef scenarios that range from coral-dominated
communities to rapidly eroding rubble banks. Notably, none of their
scenarios considers the capacity for corals to adapt. The authors
dismiss adaptation because “[r]eef-building corals have relatively long
generation times and low genetic diversity, making or slow rates of
adaptation [relative to rates of change].” We think the possibility of
adaptation deserves a second look.
In the absence of longterm demographic studies to detect temporal
trends in life history traits, predicting rates of adaptation, and
whether they will be exceeded by rates of environmental change, is pure
speculation. Indeed, where such data are available for terrestrial
organisms they demonstrate that contemporary evolution in response to
climate change is possible (7).
There's another coral story in The Herald Sun: Scientists find corals flourishing on Bikini Atoll
Phytoplankton Calcification in a High-CO2 World
Ocean acidification in response to rising atmospheric CO2 partial
pressures is widely expected to reduce calcification by marine
organisms. From the mid-Mesozoic, coccolithophores have been major
calcium carbonate producers in the world’s oceans, today accounting for
about a third of the total marine CaCO3 production. Here, we present
laboratory evidence that calcification and net primary production in
the coccolithophore species Emiliania huxleyi are significantly
increased by high CO2 partial pressures. Field evidence from the deep
ocean is consistent with these laboratory conclusions, indicating that
over the past 220 years there has been a 40% increase in average
coccolith mass. Our findings show that coccolithophores are already
responding and will probably continue to respond to rising atmospheric
CO2 partial pressures, which has important implications for
biogeochemical modeling of future oceans and climate.
Read more at Dot Earth: Some Plankton Thrive With More CO2 Source
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