Friday, 25 Feb 2005

As doctors, veterinarians, and biologists join forces to fight diseases like monkeypox, malaria, Ebola, and SARS that pass from animals to human hosts, a new field is emerging: conservation medicine. Researchers say human activities -- everything from chopping down forests and spewing greenhouse gases to globe-trotting and bolstering international trade -- may be causing these infectious diseases and many more to spread to ever wider human populations. Jim Motavalli investigates the intersection of disease and environmental destruction -- today on the Grist Magazine website.

People, People Who Breed People

Better make room -- world population to hit 9.1 billion by 2050

There will be 9.1 billion people on this li'l planet of ours by 2050, according to revised U.N. population figures released yesterday. That's a 40 percent increase from today's mere (!) 6.5 billion. While population in developed countries is expected to remain largely stable at 1.2 billion -- mainly due to immigration, as their native birth rates are declining -- the world's 50 poorest countries will see their numbers more than double. At the same time, life expectancy in southern Africa has declined from 62 years in 1995 to 48 years in 2000-2005, and is projected to hit a low of 43 before a slow recovery. That means Africans are being born and lost to AIDS at a rate almost incomprehensible to comfortable Westerners. Speaking of which, U.S. population is set to rise from 298 million in 2005 to 394 million in 2050, with immigration the main driver of growth. Meanwhile, India will probably surpass China as the world's most populous nation in coming decades, due to higher birth rates. "It is going to be a strain on the world," said Hania Zlotnik, U.N. Population Division director and master of understatement.


Turns out Grist readers have a healthy appetite for information about green building; they want to know what the best and worst companies are, how to choose products for their homes, and where to learn more about green building standards and techniques. Bill Walsh, founder of the Healthy Building Network, is just the man to sate their hunger with helpful tidbits about the dangers of the vinyl industry, the significance of the LEED rating system, and more -- in InterActivist, today on the Grist Magazine website.

Dam

Hydropower a major greenhouse-gas producer, researchers say

Although hydroelectric power is often heralded as a green alternative to fossil fuels like coal, scientists now say that in terms of greenhouse-gas production, hydro projects may be just as damning. Ahem. New research reveals that the initial flooding involved in creating hydroelectric dams releases large amounts of carbon from plants that are killed in the process. Then, leftover plant matter and other plants killed when water levels rise decompose and release methane into the atmosphere. These greenhouse-gas emissions add up -- in the case of one Brazilian dam project studied, emissions released over a year were more than triple what would have been produced by burning oil. The Intergovernmental Panel on Climate Change is considering counting some hydro-related emissions toward countries' allotments, but its proposed new guidelines would not count methane in this group, so some scientists say the proposals don't go far enough.


Does a devotion to environmental quality come at the expense of living wages and affordable health care for working-class people? Is there a finite pot of money that all environmental groups must fight for amongst themselves? A group of young environmental leaders convened by Grist this week to discuss the future of the green movement thinks not. Bringing perspectives from areas as diverse as inner-city environmental justice and Native American culture (even a chamber of commerce!), our Environmental Leadership Program representatives hash it out over email -- in Dispatches, today on the Grist Magazine website. Join the discussion yourself -- in Gristmill.