Climate stabilization: Planting trees cannot replace cutting CO2 emissions

Growing plants and then storing the CO2 they have taken up from the atmosphere is no viable option to counteract unmitigated emissions from fossil fuel burning, a new study shows. The plantations would need to be so large, they would eliminate most natural ecosystems or reduce food production if implemented as a late-regret option in the case of substantial failure to reduce emissions. However, growing biomass soon in well-selected places with increased irrigation or fertilization could support climate policies of rapid and strong emission cuts to achieve climate stabilization below 2 degrees Celsius.

Flat Antarctica – Land height could help explain why Antarctica is warming slower than the Arctic

Temperatures in the Arctic are increasing twice as fast as in the rest of the globe, while the Antarctic is warming at a much slower rate. A new study published in Earth System Dynamics, a journal of the European Geosciences Union, shows that land height could be a “game changer” when it comes to explaining why temperatures are rising at such different rates in the two regions.

Water Efficiency in Rural Areas is Getting Worse, Even as it Improves in Urban Centers

A nationwide analysis of water use over the past 30 years finds that there is a disconnect between rural and urban areas, with most urban areas becoming more water efficient and most rural areas becoming less and less efficient over time.

ALMA Eyes Icy Ring around Young Planetary System

An international team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) has made the first complete millimeter-wavelength image of the ring of dusty debris surrounding the young star Fomalhaut. This remarkably well-defined band of rubble and gas is likely the result of exocomets smashing together near the outer edges of a planetary system 25 light-years from Earth.

UCLA-led researchers track groundwater loss during drought in California's Central Valley

A new study by researchers from UCLA and the University of Houston reveals significant groundwater loss in California’s Central Valley during the recent drought and sparks questions of sustainability for the important agricultural area.

Researchers tracked net groundwater consumption in the Central Valley from 2002 to 2016, which included two droughts, one from 2007 to 2009 and the more severe drought from 2012 to 2016. California’s Central Valley is more than 18,000 square miles from the coast to the Sierra Nevada Mountains and is one of the largest agricultural hubs in the United States, providing more than half of the U.S. fruit, vegetable and nut crops.

A Recipe For Concrete That Can Withstand Road Salt Deterioration

Road salt, used in copious helpings each winter to protect them from ice and preserve safe driving conditions, is slowly degrading the concrete they’re made of. Engineers have known for some time that calcium chloride salt, commonly used as deicer, reacts with the calcium hydroxide in concrete to form a chemical byproduct that causes roadways to crumble.

Earth's atmosphere more chemically reactive in cold climates

Unseen in the air around us are tiny molecules that drive the chemical cocktail of our atmosphere. As plants, animals, volcanoes, wildfires and human activities spew particles into the atmosphere, some of these molecules act as cleanup crews that remove that pollution.

The main molecules responsible for breaking down all these emissions are called oxidants. The oxygen-containing molecules, mainly ozone and hydrogen-based detergents, react with pollutants and reactive greenhouse gases, such as methane.

Scientists Begin to Unlock Secrets of Deep Ocean Color from Organic Matter

About half of atmospheric carbon dioxide is fixed by ocean's phytoplankton, mainly picocyanobacteria, through a process called photosynthesis. Picocyanobacteria are tiny, unicellular microorganisms that are abundant and widely distributed in freshwater and marine environments. A large portion of biologically fixed carbon is formed by picocyanobacteria at the sea surface and then transported to the deep ocean. But what remains a mystery is how colored dissolved organic matter which originates from plant detritus (either on land or at sea) makes it into the deep ocean. A team of scientists from the University of Maryland Center for Environmental Science and around the world potentially found a viable marine source of this colored material.

During heat waves, urban trees can increase ground-level ozone

Planting trees is a popular strategy to help make cities “greener,” both literally and figuratively. But scientists have found a counterintuitive effect of urban vegetation: During heat waves, it can increase air pollution levels and the formation of ozone. Their study appears in ACS’ journalEnvironmental Science & Technology.

Previous research has shown that planting trees in cities can have multiple benefits, including storing carbon, controlling storm water and cooling areas off by providing shade. This has spurred efforts in cities across the U.S. and Europe to encourage the practice. However, it’s also known that trees and other plants release volatile organic compounds, or VOCs, that can interact with other substances and contribute to air pollution. And when it’s hot, plants release higher levels of VOCs. Galina Churkina and colleagues wanted to investigate what effects heat waves and urban vegetation might have on air pollution.

When Birds of a Feather Poop Together

At the Maji Agricultural Reservoir in Wonju, Gangwond-do, South Korea, that someone is Tae Kwon Lee. Lee regularly jogs around the reservoir. One day he noticed large black birds completely covering the small island in the lake. The black birds were great cormorants, a type of large water bird, and the trees on the islet were completely covered in the birds’ feces. As time passed, Lee made another observation: the lake suffered a severe algal bloom.

Algal blooms deplete oxygen in lakes, produce toxins, and end up killing aquatic life in the lake. This sequence of events got Lee wondering: Did the bird feces cause or contribute to the algal bloom?