As a result of increasing atmospheric carbon dioxide concentrations, the chemistry of the Southern Ocean is expected to change so fast over the next few decades that tiny creatures at the base of the food web may soon struggle to form their shells. New research by scientists from UH Mānoa and the University of Alaska, Fairbanks (UAF) finds that, for some organisms, the onset of such critical conditions will be so abrupt, and the duration of events so long, that adaption may become impossible.The study, published this week in the journal Nature Climate Change, uses a number of Earth System Models to explore how the uptake of anthropogenic carbon dioxide and the resulting ocean acidification will affect the Southern Ocean over the next century. 

A recently published study on how natural and man-made sources of nitrogen are recycled through the Lake Tahoe ecosystem provides new information on how global change may affect the iconic blue lake.“High-elevation lakes, such as Lake Tahoe, are sentinels of climate change,” said Lihini Aluwihare, associate professor of geosciences at Scripps Institution of Oceanography (SIO) at UC San Diego and co-author of the study. “Small changes in the lake's chemistry can have big impacts on the entire ecosystem.”Lake Tahoe's nitrogen concentration is one of several factors that helps maintain its crystal clear waters. To keep Tahoe blue in the future, the researchers say it's important to keep a close eye on the nitrogen balance in the ecosystem over time.