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
Jennifer Marohasy BSc PhD has worked in industry and government. She is currently researching a novel technique for long-range weather forecasting funded by the B. Macfie Family Foundation.