Climate Change Weekly Roundup: 07/02/12

Publication – Environmental News Network
Date: June 26, 2012

Sea Level Rise may continue for Centuries

If global warming continues, sea levels around the world can be expected to rise by several meters in coming centuries, according to new research.

The study gives a comprehensive projection for this long perspective, based on observed sea-level rise over the past millennium, as well as on scenarios for future greenhouse-gas emissions.

“Sea-level rise is a hard to quantify, yet critical risk of climate change,” Michiel Schaeffer of Climate Analytics and Wageningen University, lead author of the study, told ENN. “Due to the long time it takes for the world’s ice and water masses to react to global warming, our emissions today determine sea levels for centuries to come.”

The findings suggest that even at relatively low levels of global warming, sea-level rise may still rise. The study also demonstrates the benefits of reducing greenhouse-gas emissions.

“Limiting global warming to below 1.5 degrees Celsius and subsequent temperature reductions could halve sea-level rise by 2300, compared to a 2-degree scenario. If temperatures are allowed to rise by 3 degrees, the expected sea-level rise could range between 2 and 5 metres, with the best estimate being at 3.5 metres” according to the article.

Publication – Environmental News Network
Date: June 26, 2012

Wind Energy Creates a Warming Effect, Study Finds

Scientists recently discovered an unexpected link between wind farms and rising land surface temperatures. Surprisingly, the scientist found that wind farms may stir air in an atmospheric boundary layer a bit too much — enough to produce a noticeable warming effect after the sundown.

The study is one of the first ones to consider interactions between wind turbines and the atmospheric boundary layer near the land surface, according to ENN.

A team of scientists from State University of New York at Albany, and several other institutions, present long-term observational evidence of the effects of wind farms on surface temperatures. Over the span of nine years, they carefully observed land surface temperatures around four wind farms in west-central Texas. Guided by the satellite data, the team found that wind farms are responsible for “a significant warming trend of up to 0.72°C per decade, particularly at night-time”.

Publication – NewsWise
Date: June 27, 2012

Dying Trees in Southwest Set Stage for Erosion, Water Loss in Colorado River

New research finds that drought and mountain pine beetle attacks are the primary forces that have killed more than 2.5 million acres of pinyon pine and juniper trees in the American Southwest during the past 15 years, setting the stage for further ecological disruption, according to NewsWise.

The widespread decline in the two tree species is a special concern, scientists say, because they are some of the last trees that can hold together a fragile ecosystem, nourish other plant and animal species, and prevent serious soil erosion.

The major form of soil erosion in this region is wind erosion, according to NewsWise. Dust blowing from eroded hills can cover snowpacks, cause them to absorb heat from the sun and melt more quickly, and further reduce critically-short water supplies in the Colorado River basin.

Publication – Science Daily
Date: June 27, 2012

Half of Inhaled Soot Particles from Diesel Exhaust, Fires Gets Stuck in the Lungs

The exhaust from diesel-fueled vehicles, wood fires and coal-driven power stations contains small particles of soot that are released into the atmosphere. The soot is devastating for the climate, but also for human health. For the first time, researchers have studied in detail how diesel soot gets stuck in the lungs.

Researchers found that more than half of all inhaled soot particles remain in the body.

The figure of more than half is higher than for most other types of particles. For example “only” 20 per cent of another type of particle from wood smoke and other biomass combustion gets stuck in the lungs, according to Science Daily. One explanation is that diesel soot is made up of smaller particles and can therefore penetrate deeper into the lungs, where it is deposited.

The study was made on diesel particles – which mainly consist of soot. Ten healthy people volunteered for the the study.

“Findings of this kind can be extremely useful both for researchers to determine what doses of soot we get into our lungs out of the amount we are exposed to, and to enable public authorities to establish well-founded limits for soot particles in outdoor air,” Jenny Rissler, researcher in aerosol technology at Lund University’s Faculty of Engineering and responsible for publishing the study, told Science Daily.

Publication – Science Daily
Date: June 28, 2012

Africa’s Savannas May Become Forests by 2100, Study Suggests

A new study suggests that large parts of Africa’s savannas may be forests by 2100.

The study suggests that fertilization by atmospheric carbon dioxide is forcing increases in tree cover throughout Africa, according to ENN. A switch from a savanna to a forest occurs when a critical threshold of CO2 concentration is exceeded, yet each site has its own critical threshold. The implication is that each savanna will switch at different points in time, thereby reducing the risk that a synchronous shock to the earth system will emanate from savannas.

Complex tropical grasslands like savannas and forests are expected to respond sensitively to climate and atmospheric changes. This is because the main players, grasses and trees, differ fundamentally in their response to temperature, carbon dioxide supply and fire and are in an unrelenting struggle for the dominance of the savanna complex. The outcome of this struggle determines whether vast portions of the globe’s tropical and sub-tropical regions are covered with grasslands, savannas or forests. In the past such shifts in dominance have played out in slow motion, but the current wave of atmospheric changes has accelerated the potential rate of change.

Have you seen breaking climate change news or discussion that should be included in our next “Roundup?”  Let us know!