The collision of North and South America changed the Earth's climate dramatically – and may have happened far earlier than we thought.

In the high-altitude desert of the Indian trans-Himalayas, one man is buying time for villagers suffering from global warming by creating artificial glaciers.

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Thanks to a little help from researchers equipped with satellite imagery, farmers in Raj Samadhilyia, a tiny village in Gujarat, have been able to do a better job of capturing, managing, and using the precious water provided by scanty rains.

Analysts estimate that nearly 2 million of Uganda's 31 million people experience food insecurity due to supply problems or rising prices. Nearly 80% of the people in some regions depend on food aid to survive. Such problems could worsen as Uganda's population, which has been increasing at more than 3% per year, surges to an estimated 100 million by 2050.

Are the Maldives doomed to disappear beneath the waves, or can a last ditch effort hold back rising sea levels?

If the planet warms by 4