Earth biosphere damaged by Gamma-ray bursts

Earth biosphere damaged by Gamma-ray bursts

Wild Card's progress: nominated

This Wild Card came from: 
Scientists/researchers

The source of this Wild Card: 
"Gamma-Ray Bursts Could Halt Photosynthesis" http://www.wired.com/wiredscience/2010/07/grb-photosynthesis-shutdown/

Likelihood timeframe and scenario features : 
now-2050+

Wild Card's description 
Gamma-ray bursts originating thousands of light-years away cause serious damage to the earth biosphere, including shutting down photosynthesis in the oceans at depths of up to 260 feet. Gamma-ray bursts are linked to mass extinctions on Earth in the far past. They carry energies equivalent to billions of nuclear bombs going off at once.