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Global warming could make world more 'fragrant'.
A major scientific review has indicated that as a result of climate change, the world will become more 'fragrant'.
As CO2 levels increase and the world warms, land use, precipitation and the availability of water will also change.
According to BBC News, in response to all these disruptions, plants will emit greater levels of fragrant chemicals called biogenic volatile organic compounds (BVOCs).
That will then alter how plants interact with one another and defend themselves against pests, according to a major scientific review.
The world may already be becoming more fragrant, as plants have already begun emitting more smelly chemicals, according to the scientists leading the review.
"The increase is exponential," said Professor Josep Penuelas, of the Global Ecology Unit at the Autonomous University of Barcelona, Spain.
"It may have increased already by 10 percent in the past 30 years and may increase 30 to 40 percent with the two to three degrees (Celsius) warming projected for the next decades," he added.
BVOCs are routinely emitted by plants into the atmosphere.
All play vital roles in helping plants grow and metabolise, communicate with one another and reproduce, and protect or defend themselves from herbivores such as browsing mammals or insect pests.
But plants emit different levels of such compounds depending on environmental conditions.
While significant research has been done to assess the impact of global warming on further CO2 exchange in the atmosphere, little focus has been given to how changing temperatures will alter emissions of important compounds such as BVOCs.
So, Professor Penuelas and Dr Michael Staudt of the Centre for Functional Ecology and Evolution in Montpellier, France, conducted a major review of how climate change will alter the expression of these compounds.
"Based upon the work reviewed, we can be reasonably sure that climate and global change in general will have an impact on BVOC emissions," they said.
"The most likely overall impact is an increase in BVOC emissions mostly driven by current warming, and that the altered emissions will affect their physiological and ecological functions and their environmental role," they added.
In particular, they said that higher temperatures will cause plants to produce more BVOCs, and also lengthen the growing season of many species, further adding to the BVOCs produced.
By enhancing the activity of BVOC synthesising enzymes, and making it easier for such compounds to diffuse into the air, rising temperatures will cause a sharp, exponential increase in BVOCs.
Melting icebergs causing sea level rise.
Scientists have discovered that ice floating in the polar oceans is melting, causing sea levels to rise. The research is the first
assessment of how quickly floating ice is being lost.
According to Archimedes' principle, any floating object displaces its own weight of fluid. For example, an ice cube in a glass of water does not cause the glass to overflow as it melts.
But because sea water is warmer and more salty than floating ice, changes in the amount of this ice are having an effect on global sea levels.
The loss of floating ice is equivalent to 1.5 million Titanic-sized icebergs each year. However, the study shows that spread across the global oceans, recent losses of floating ice amount to a sea level rise of just 49 micrometers per year - about a hair's breadth.
Andrew Shepherd, professor at the University of Leeds, who led the study, said it would be unwise to discount this signal.
"Over recent decades there have been dramatic reductions in the quantity of earth's floating ice, including collapses of Antarctic ice shelves and the retreat of Arctic sea ice," Shepherd said.
"These changes have had major impacts on regional climate and, because oceans are expected to warm considerably over the course of the 21st century, the melting of floating ice should be considered in future assessments of sea level rise," he added.
Shepherd and his team used a combination of satellite observations and a computer model to make their assessment.
They looked at changes in the area and thickness of sea ice and ice shelves, and found that the overall signal amounts to a 742 cubic kilometres per year reduction in the volume of floating ice.
Because of differences in the density and temperature of ice and sea water, the net effect is to increase sea level by 2.6% of this volume, equivalent to 49 micrometers per year spread across the global oceans, a Leeds release said.
The greatest losses were due to the rapid retreat of Arctic Sea ice and to the collapse and thinning of ice shelves at the Antarctic Peninsula and in the Amundsen Sea.
The findings were published this week in Geophysical Research Letters.
Global warming helping trees grow faster.
Global warming is helping trees to grow at a faster rate now than they have done in the past 200 years due to higher temperatures and
more carbon dioxide into the atmosphere, American researchers have claimed.
After studying the growth of 55 forests in the eastern United States for over 20 years, the scientists from the Smithsonian Environmental Research Center in Maryland found that the recent tree growth "greatly exceeded the expected growth".
They suggested that global warming is helping trees to grow faster as it brings higher temperatures, longer growing seasons and more carbon dioxide into the atmosphere.
In one forest, studied by the researchers, an extra 1.8 tonnes of timber per acre is appearing each year. "The trees, in Maryland, are sprouting up more quickly than at any time in the past 225 years," the scientists said.
Lead researcher Geoffrey Parker said: "We made a list of reasons why these forests could be growing faster and then ruled half of them out".
"The best explanation was a response to climate change, he was quotes as saying by the journal Proceedings of the National Academy of Sciences.
In the past 22 years, carbon dioxide levels where the study was conducted had risen 12 per cent, the average temperature had increased by nearly three tenths of a degree, and the growing season had lengthened by 7.8 days.
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