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'Planetary boundaries' is an idea that was showcased by Johan Rockström, executive director of the Stockholm Resilience Centre, in Nature in 2009, and refers to limits to the use of nine of the Earth's resources, ranging from activities that generate carbon dioxide to land use, the loading of atmosphere with aerosols and the use of oceans.

"Rising sea levels, more intense storms, changes in ocean chemistry due to air and water pollution - all these stress coral reefs," observed Steve Palumbi, an expert on corals with the Center for Ocean Solutions and the chief organizer in developing the consensus statement. "At least 25 percent of the world's coral reefs have been degraded. Because of the global origin of climate change, the only way to tackle this is through a worldwide effort."

But the data from three independent satellites this July, analyzed by NASA and university scientists, showed that in less than a week, the amount of thawed ice sheet surface skyrocketed from 40 percent to 97 percent.

In over 30 years of observations, satellites have never measured this amount of melting, which reaches nearly all of Greenland's surface ice cover.