Learn the distinctions between simple and stratified random sampling. Understand how researchers use these methods to accurately represent data populations.

For decades, scientists have relied on a chemical fingerprint inside water molecules to determine where plants get their moisture. The method shaped our understanding of drought resilience, ...

The International Atomic Energy Agency (IAEA) led a team of international experts in conducting seawater sampling and fishery product selection this week near the Fukushima Daiichi Nuclear Power ...

Detecting microplastics and identifying plant stress at an early stage -- this and much more can now be done thanks to a new method based on near-infrared light measurements. It is inexpensive and ...

National security, unlocked. Each Thursday, host Mary Louise Kelly and a team of NPR correspondents discuss the biggest national security news of the week. With decades of reporting from battlefields ...

Environmental Protection Agency Administrator Lee Zeldin in California last week. (Mario Tama/Getty Images) Environmental Protection Agency Administrator Lee Zeldin on Thursday is expected to announce ...

The Environmental Protection Agency enforces the country's environmental laws. But a new report shows the Trump EPA has initiated a record low number of actions against polluters, compared to past ...

The Trump administration has repealed an EPA rule that classified carbon dioxide and five other greenhouse gases as a threat to public health. The endangerment finding underpinned regulations that set ...

The Environmental Protection Agency scrapped the agency’s landmark 2009 global warming “endangerment finding,” breaking with the long-standing scientific consensus that global warming poses a risk to ...

The agency is racing to repeal a scientific finding that requires it to fight global warming. Experts say the goal is to get the matter before the justices while President Trump is still in office. By ...

The greenhouse gases emitted from sources like cars, trucks and power plants, major contributors to climate change, will no longer be regulated by the federal government, following an announcement ...

Add Yahoo as a preferred source to see more of our stories on Google. A welder uses an angle grinder on metal inside a factory, sending sparks flying across the workshop. Photo: Hassan yahia / Pexels ...