In 1979, Egyptian President Anwar Sadat famously said that “the only matter that could take Egypt to war again is water.” Sadat’s message was clear: the Nile is a matter of national security for Egypt.

Indeed, Egypt relies on the Nile for 95 percent of its water. But it is not the only state with an interest in the world’s longest river. There are 11 states in the Nile River basin, which stretches from Africa’s Great Lakes region – Tanzania, Uganda, Kenya, Rwanda, Burundi, and the Democratic Republic of the Congo – to the Ethiopian and Eritrean highlands through South Sudan, Sudan, and Egypt to the Mediterranean Sea.

“Population-health-environment [PHE] connections have really been a focus of ours here at the Wilson Center for the last 15 years,” said outgoing ECSP Director Geoff Dabelko in an interview at the Wilson Center. The goal of ECSP’s project – HELPS (health, environment, livelihoods, population, and security) – is “really trying to understand these issues together.”

Over the next two decades, as many as three billion people will join the middle class, even as billions more live without electricity, modern cooking fuel, and safe and reliable access to food and water. Resources are becoming more scarce and more difficult to extract, and combined with environmental factors ranging from climate change to soil erosion, those changes will make meeting middle class demand all the more difficult while leaving the world’s poorest more vulnerable to price shocks and resource shortages. In a recent report, the McKinsey Global Institute concludes that nothing less than a “step change” in how resources are managed will be required if individuals, businesses, and governments are to overcome these trends and pave the way for a more sustainable and equitable future.

Specifically attributing a particular weather event to climate change has been difficult – as one famous analogy goes, it’s like determining which of Mark McGwire’s home runs were because of steroids and which weren’t. But climate attribution science is slowly becoming more accurate and accepted. In “Explaining Extreme Events of 2011 From a Climate Perspective,” a new study appearing in July’s Bulletin of the American Meteorological Society, editors Thomas C. Peterson, Peter A. Stott, and Stephanie Herring provide a review of six extreme weather events from last year and offer “some illustrations of a range of possible methodological approaches” to the process of attribution. Among their conclusions, the editors note that, due to climate change, the extreme heat and drought that suffocated Texas in 2011 was 20 times more likely to occur than 40 years earlier. However, the devastating floods that swept across Thailand last year are blamed on a number of other non-climatic factors.

The original version of this article, by Christina Larson, appeared on Yale Environment 360.

Bouncing along bad roads in a jeep through central Mongolia, with bright blue skies and high clouds overhead, we drive for miles through a treeless landscape, passing only dry grasslands dotted with cattle and white yurts. But as we head north – myself, two U.S. scientists, and one Mongolian forestry expert – we begin to notice Siberian pine and larch growing on the northern slopes of rolling hills, but not the southern slopes, and at some elevations, but not others. In water-scarce Mongolia, as my travel companion Neil Pederson of Columbia University’s Lamont-Doherty Earth Observatory explained, the precarious growth of trees is limited by temperature and moisture availability; small variations – northern slopes are slightly cooler and wetter – can make all the difference.

In the “first spatially explicit comparison of groundwater use, availability, and environmental flow for aquifers globally,” a new article in Nature finds that the “size of the global groundwater footprint is currently about 3.5 times the actual area of aquifers.” An aquifer’s footprint is the theoretical size it would need to be to sustainably support use at its current rate, so groundwater footprints being much larger than their corresponding aquifers is a sign of overuse.

Climate change “has been thought of in many quarters as something that affects folks ‘over there,’ and not as much domestically, and I think that’s a mistake,” said ECSP’s Geoff Dabelko in a recent podcast with the Zurich-based International Relations and Security Network. “I think folks are coming to a realization that there are very high economic, political, and ultimately security stakes for the United States.”

The original version of this article, by Michael Kugelman, appeared on Dawn.

There’s been much discussion lately about the “water kit,” a mysterious contraption that a purported Pakistani engineer insists will enable cars to use water as fuel.

Yet missing from this debate is a basic but critical fact: Pakistan is dangerously water-deficient. Per capita availability hovers just above the scarcity threshold of 1,000 cubic meters. In several decades, availability could plummet to 550 cubic meters.