Category Environment/Geology

Abiogenesis: blue-green algae in a hot spring, Yellowstone National Park

Earth’s oxygen-rich atmosphere emerged in whiffs from a kind of blue-green algae in shallow oceans around 2.5 billion years ago, according to new research from Canadian and US scientists. These whiffs of oxygen likely happened in the following 100 million years, changing the levels of oxygen in Earth’s atmosphere until enough accumulated to create a permanently oxygenated atmosphere around 2.4 billion years ago – a transition widely known as the Great Oxidation Event.

The team presents new isotopic data showing that a burst of oxygen production by photosynthetic cyanobacteria temporarily increased oxygen concentrations in Earth’s atmosphere...

Space scene (stock image). Earth’s equatorial regions are largely unstudied and more susceptible to disruptive space weather than previously thought, which should prompt scientists to examine the infrastructure and economic implications on countries near the equator. Credit: © frenta / Fotolia

Dr Brett Carter of RMIT SPACE Research Centre and his team found these equatorial electrical disruptions threaten power grids in SE Asia, India, Africa and South America, where protecting electricity infrastructure from space shocks has not been a priority.

“Massive space weather events have crashed power grids across North America and Europe, but we have found that often with little warning, smaller events strike in equatorial regions more frequently than previously thought,” Carter said...

Sherri Burks in Dallas loaded her dishwasher in preparation for the 9 p.m. start of free hours of electricity from TXU Energy. Credit Brandon Thibodeaux for The New York Times

Something amazing is happening in Texas right now. Wind power has become so cheap and abundant that utilities are actually giving it away for free during night time hours. This has lead to many people conserving power during the day, and running appliances at night, when the wind blows the hardest.

Texas has more wind power than any other state, accounting for roughly 10% of the state’s generation. Alone among the 48 contiguous states, Texas runs its own electricity grid that barely connects to the rest of the country, so the abundance of nightly wind power generated here must be consumed here.

Wind blows most stro...

NASA’s GRACE satellites (artist’s concept) measured Atlantic Ocean bottom pressure as an indicator of deep ocean current speed. In 2009, this pattern of above-average (blue) and below-average (red) seafloor pressure revealed a temporary slowing of the deep currents. Credits: NASA/JPL-Caltech

A team of NASA and university scientists has developed a new way to use satellite measurements to track changes in Atlantic Ocean currents, which are a driving force in global climate. The finding opens a path to better monitoring and understanding of how ocean circulation is changing and what the changes may mean for future climate.

In the Atlantic, currents at the ocean surface, eg Gulf Stream, carry sun-warmed water from the tropics NE. As the water moves through colder regions, it sheds its heat...