Tag Archives: global warming

Trees responding to climate change: Being smart about water use

11 Jul

While the human species is struggling to collaborate on the best methods to combat climate change, trees are using their instincts to survive, a new study finds. 

Scientists with the U.S. Forest Service, Harvard University, The Ohio State University, Indiana University, and the Institute of Meteorology and Climate in Germany found that trees in the northern hemisphere have increased their water-use efficiency over the past two decades.

Water-use efficiency refers to the ratio of water loss to carbon gain during photosynthesis.

But, the increased efficiency has both positive and negative consequences.

“Our analysis suggests that rising atmospheric carbon dioxide is having a direct and unexpectedly strong influence on ecosystem processes and biosphere-atmosphere interactions in temperate and boreal forests,” Dave Hollinger, a plant physiologist with the U.S. Forest Service’s Northern Research Station, and one of the co-authors of the study said.

Hollinger explained that the change can result in more timber for building as well as a greater supply of available freshwater which could reduce the harshness of droughts in some parts of the world. However, high water-use efficiency also results in warmer temperatures and increased dryness in the air. In addition, the recycling of precipitation is hindered, therefore causing more freshwater runoff which could  increase the risk of droughts in places that rely on the water transpired in other areas.

The study, “Increase in forest water-use efficiency as atmospheric carbon dioxide concentrations rise,” was published online today in the journal Nature.

Climate change may change the way we eat, study shows

2 Nov

A new study released Wednesday by the Consultative Group on International Agricultural Research Research (CGIAR) Program on Climate Change, Agriculture and Food Security (CCAFS) shows that food and agriculture production accounts for almost 29 percent of greenhouse gas emissions, which are contributing to climate change. This number, 17,000 megatonnes of carbon dioxide annually, is alarming to scientists, who previously thought the number was much lower.

Food’s carbon “footprint” has major implications for the way food is produced and distributed, and developing countries are most at risk and may have to change the way they eat drastically.

In addition, as the earth starts to warm, key crops like maize, rice and wheat will decrease due to higher temperatures and rainfall becomes unpredictable. The researchers said this new finding shows how urgent climate change mitigation is, not only for the environment, but for food security. Continue reading

Oceans’ “sound systems” may improve due to increased acidity

19 Oct

By the year 2100, whale vocals, which occur in a low-frequency sound range less than 200 hertz, could travel twice as far.

By the year 2100, scuba divers may have the luxury of hearing in the water with the same clarity as land — if the oceans are still in shape for recreation.

Research shows that increased ocean acidity, which is caused by excess CO2 in the atmosphere combining with water to create carbonic acid, may change the acoustical properties of the water. Continue reading

When it comes to climate change, uncertainty is the enemy

16 Oct

Uncertainty is a common word when it comes to scientific research and, in many cases, unavoidable. But, the public doesn’t like this word and in politics it poses an opportunity for debate and polarization. The science related to climate change demonstrates this perfectly.

According to new research at the University of Gothenberg and Columbia University, the current climate threshold that states an increase in global temperature should be below 2 degrees Celsius, is not helping combat the problem. In fact, it may be having an adverse effect.

The problem is that the threshold number doesn’t stem from pure science, but instead is determined by Nature.

The research showed that if this number was proven without any uncertainty, then negotiations would go smoothly and countries would be happy to participate in collective efforts toward a greener and cooler planet. The problem is however, that this “certain” number that is being looked for does not exist. There will always be uncertainty.

“Climate negotiations are more complex that the game played by the participants in our experiment. The basic incentive problem, however, is the same and our research shows that scientific uncertainty about the dangerous threshold changes behavior dramatically,” Astrid Dannenberg, Postdoc researcher at the Environmental Economics Unit, said in a press release.

It may be for this reason that the UN centered the negotiations around the 2 degree celsius mark, but according to Professor Scott Barrett, Columbia University, the outlook looks dim. He suggests alternatives for negotiations that do not depend on an uncertain threshold.

“We will not know until 2020 if the Copenhagen Accord pledges will be met, but if our results are a reliable guide, countries may end up emitting even more than they pledged – with potentially profound and possibly irreversible consequences. Our research suggests that negotiators should focus their attention on alternative strategies for collective action, such as trade restrictions or technology standards,” Barrett said in a press release.