Study shows three times more mercury in upper ocean since Industrial Revolution
Although the days of odd behavior among hat makers are a thing of the past, the dangers mercury poses to humans and the environment persist today.
Mercury is a naturally occurring element as well as a by-product of such distinctly human enterprises as burning coal and making cement. Estimates of “bioavailable” mercury—forms of the element that can be taken up by animals and humans—play an important role in everything from drafting an international treaty designed to protect humans and the environment from mercury emissions, to establishing public policies behind warnings about seafood consumption. (more…)
Potential for Storing Meltwater Important for Calculating Sea-Level Rise
Researchers at the University of Utah have discovered a new aquifer in the Greenland Ice Sheet that holds liquid water all year long in the otherwise perpetually frozen winter landscape. The aquifer is extensive, covering 27,000 square miles.
The reservoir is known as a “perennial firn aquifer” because water persists within the firn – layers of snow and ice that don’t melt for at least one season. Researchers believe it figures significantly in understanding the contribution of snowmelt and ice melt to rising sea levels. (more…)
AUSTIN, Texas — Scientists at the University of Texas at Austin’s Institute for Geophysics helped develop a blueprint for a possible future NASA lander mission to Europa, an icy moon of Jupiter that has a global ocean covered by an ice shell. Europa’s large reservoir of liquid water has long enchanted planetary scientists with the possibility of harboring life. Many experts believe it to be the most likely place in our solar system besides Earth to host life today. The proposed mission is designed to assess the moon’s habitability by studying its surface composition, ice shell, ocean and geology.
Don Blankenship, senior research scientist at the institute, is part of the science definition team commissioned by NASA to draft the report, which appears in the August 2013 issue of Astrobiology. Blankenship and two colleagues — Krista Soderlund, postdoctoral fellow at the institute; and Britney Schmidt, formerly a postdoctoral fellow at the institute, now assistant professor at the Georgia Institute of Technology — developed a part of the mission scenario that would use sound waves to study the moon’s icy shell, deep ocean and possible shallow lakes. (more…)
ANN ARBOR— An international team of scientists, including a University of Michigan graduate student, has demonstrated that a clear difference exists between the marine microbial communities in the Southern and Arctic oceans, contributing to a better understanding of the biodiversity of marine life at the poles.
The most comprehensive comparison of microbial diversity at both of Earth’s polar oceans showed that about 75 percent of the organisms at each pole are different. This insight sheds light on newly recognized biodiversity patterns and reinforces the importance of studying Earth’s polar regions in the face of a changing climate. And it highlights the need for further research on the impacts of sea ice, seasonal shifts and freshwater input in both regions. (more…)
Ocean currents may mitigate warming near handful of equatorial islands
Scientists predict ocean temperatures will rise in the equatorial Pacific by the end of the century, wreaking havoc on coral reef ecosystems.
But a new study shows that climate change could cause ocean currents to operate in a way that mitigates warming near a handful of islands right on the equator.
Those islands include some of the 33 coral atolls that form the nation of Kiribati. This low-lying country is at risk from sea-level rise caused by global warming. (more…)
Billions of years ago, an astounding evolutionary event occurred: certain bacteria became obliged to live inside other cells, thus starting a chain of events that resulted in what is now the mitochondria, an organelle found in all eukaryotic cells. A recent study by researchers at the University of Hawaiʻi at Mānoa and the Oregon State University (OSU) provides strong evidence that mitochondria share a common evolutionary ancestor with a lineage of marine bacteria known as SAR11, arguably the most abundant group of microorganisms on Earth.
“This is a very exciting discovery,” said Michael Rappe, Associate Researcher at the Hawaiʻi Institute of Marine Biology in the School of Ocean and Earth Science and Technology (SOEST) at UH Mānoa. “The results that we present make sense in a lot of ways: the physiology of SAR11 makes them more apt to be dependent on other organisms, and based on the contemporary abundance of SAR11 in the global ocean, the ancestral lineage may have also been abundant in the ancient ocean, increasing encounters between this bacterial lineage with the host of the original symbiosis event.” (more…)
The contribution of Greenland to global sea level change and the mapping of previously unknown basins and mountains beneath the Antarctic Ice Sheet are highlighted in a new film released by Cambridge University this morning.
The work of glaciologist Professor Julian Dowdeswell, Director of Cambridge University’s Scott Polar Research Institute, is the focus of This Icy World, the latest film in the University’s Cambridge Ideas series. (more…)
*Geobiologists uncover Davy Jones Locker of fossils near small village in south China*
Almost 600 million years ago, before the rapid evolution of life forms known as the Cambrian explosion, a community of seaweeds and worm-like animals lived in a quiet deep-water niche near what is now Lantian, a small village in south China.
Then they simply died, leaving some 3,000 nearly pristine fossils preserved between beds of black shale deposited in oxygen-free and unbreathable waters. (more…)
