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Researchers led by Scripps Institution of Oceanography at the University of California San Diego have determined that major changes in plant behavior have occurred over the past 40 years, using measurements of subtle changes in the carbon dioxide (CO2) currently found in the atmosphere.

The two main isotopes, or atomic forms, of carbon are carbon-12 (12C) and carbon-13 (13C). As CO2 has risen since the late 19th century, the ratio of 13C to 12C in atmospheric CO2 has decreased. That’s in part because the CO2 produced by the combustion of fossil fuels has a low 13C/12C ratio. There are other factors in nature as well, however, that have influenced the rate of decrease in the isotopic ratio.  The measured rate of decrease in the isotopic ratio turns out to be different than what scientists previously expected.

Desert locusts are a major pest on numerous crops and pastures throughout a vast area of almost 30 million km2 covering Africa north of the equator, the Near East, the Arabian Peninsula and the Indian subcontinent. Like other locusts, desert locusts can switch from a solitary phase with low population densities during recessions (periods of calm), to a gregarious phase with high population densities during invasions, when hopper bands and swarms can devastate agriculture.

Clinicians are being warned not to ignore the increased cardiovascular health risks of those who are classed as either ‘healthy obese’ or deemed to be ‘normal weight’ but have metabolic abnormalities such as diabetes.

There are currently an estimated 4.5 billion people around the world exposed to levels of particulate air pollution that are at least twice what the World Health Organization considers safe. Yet the impact of sustained exposure to pollution on a person’s life expectancy has largely remained a vexingly unanswered question—until now.

NASA-NOAA's Suomi NPP satellite captured night-time look at Hurricane Irma as it weakened to a large tropical storm and the GOES East satellite provided a daytime view as the large storm continued moving north over Florida.