Week of 12/12/10

Dear EarthTalk: I understand that China is about to overtake the U.S. as the world’s largest global warming polluter. What is China doing to address this issue as well as its other environmental impacts as such a populous nation?

—Sophie N., Andover, MA

Actually, China passed the U.S. as the world’s leading greenhouse gas emitter back in 2006 and today produces some 17 percent of the world’s total carbon dioxide output. According to the China Daily news service, air and water pollution, combined with widespread use of food additives and pesticides, make cancer the top killer in China. Meanwhile, World Bank data show that, based on the European Union’s air quality standards, only one percent of the country’s 560 million urban inhabitants breathe air deemed safe. But many Chinese insist that all this environmental trouble is part of the cost of developing into a world superpower, and government leaders there are hesitant to impose restrictions on economic development.

Nevertheless, the Chinese are starting to take action. In December 2009 at the Copenhagen global climate talks, China announced plans to slow greenhouse gas emission increases relative to economic growth by 40-50 percent between 2005 and 2020, and use renewable fuels for 15 percent of its energy. China also committed to increasing forest cover by 40 million hectares by 2020 (forests absorb carbon dioxide).

But even with such measures, analysts say China’s carbon dioxide output will still increase a staggering 90 percent in the next decade, assuming eight percent economic growth. While international negotiators were pleased to finally secure a commitment from the Chinese, it was a far cry from the fast and binding emissions cuts many scientists say are necessary to stave off potentially cataclysmic climate change.

China passed the U.S. as the world"s leading greenhouse gas emitter back in 2006 and today produces some 17 percent of the world"s total carbon dioxide output. Pictured: A factory in China at the Yangtse River.© High Contrast, courtesy Wikipedia

Regarding other pollution, China is a signatory to the Stockholm Convention, which governs the control and phase-out of major persistent organic pollutants (POPs), including many pesticides, PCBs and other chemicals. China has committed to eliminating the production, import and use of pollutants covered under the treaty, and will establish an inventory of POP contaminated sites and remediation plans by 2015.

Other green strides China has made include 2008’s nationwide ban on plastic shopping bags. Before the ban, China was using 37 million barrels of crude oil annually to make the bags that would no doubt come back to haunt people, wildlife, land and water bodies as litter. China has also signed on to an international effort sponsored by the United Nations and the Global Environment Facility to phase out incandescent lightbulbs over the next decade in favor of more efficient varieties. China makes 70 percent of the world’s supply of lightbulbs, so the switch could have a big impact on energy usage for lighting around the world.

China is also no slouch when it comes to manufacturing green technologies and now produces more solar panels and wind turbines than any other country. And the Chinese government recently committed $216 billion in subsidies to further develop the nation’s green technology sector. A recent report by the non-profit Pew Environment Group found that in 2009 China spent two times as much as the U.S. to fund so-called "green markets," and close to 50 percent of world expenditures overall.

CONTACTS: Copenhagen Accord; Stockholm Convention; Global Environment Facility; Pew Environment Group.

Dear EarthTalk: Are the world’s amphibians still in decline and what’s being done to help them?

—Chris W., Stamford, CT

A recently updated worldwide population assessment by the International Union for the Conservation of Nature found that 32 percent of the 6,000-plus amphibian species left on the planet have declined to dangerously low levels. Pictured: A red-eyed tree frog.© Thinkstock

Unfortunately yes, amphibians are still in serious trouble around the world. A recently updated worldwide population assessment by the non-profit International Union for the Conservation of Nature (IUCN) found that 32 percent of the 6,000-plus amphibian species left on the planet have declined to dangerously low levels—and qualify for vulnerable, endangered or critically endangered status on the group’s "Red List" of at-risk wildlife.

Perhaps even more disturbing is that upwards of 160 amphibian species—some of which have been around for hundreds of millions of years—have gone extinct just in the last 25 years. Since amphibian species are particularly sensitive to environmental change, they are often the first animals to decline in areas just beginning to experience environmental degradation, and as such are considered to be important indicators of the health of the wider ecosystems surrounding them.

Scientists are hard-pressed to pick one major cause for such dramatic declines, but at least one key culprit is a fungal pathogen called "frog chytid" (Batrachochytrium dendrobatidis). According to the non-profit Amphibian Ark, frog chytid causes changes to amphibians" sensitive outer skin layer, making vital life processes—such as the absorption of water, oxygen and electrolytes—difficult or impossible. Prior to 1999 researchers hadn’t yet identified this variant of the chytid fungus, let alone the role it was playing in decimating amphibian populations. It is particularly dangerous because none of the world’s amphibians seem to be immune—even those species that survive an infestation still carry and transmit the parasite.

Frog chytid isn’t the only factor in amphibians" recent troubles. According to the AmphibiaWeb website, habitat destruction, alteration and fragmentation (with the forest goes the frogs), as well as predatory introduced species, increased exposure to UV-B radiation (likely caused by erosion of the Earth’s protective ozone layer), various forms of air and water pollution, and poaching all combine to stack the odds against amphibians. Human-induced climate change is likely playing a role in the decline as well, with rising global temperatures creating optimal conditions for the growth and spread of the frog chytid pathogen while also displacing amphibians from formerly hospitable habitat zones.

IUCN and its partners Conservation International and NatureServe have released an Amphibian Action Conservation Plan, which outlines ways that international institutions, national governments, corporations and even everyday people can take part in helping to save our frogs and their relatives. According to the plan, reducing pollution and lowering our carbon footprint is an important first step. Likewise, preserving more amphibian habitat—especially in Latin America, which has the largest number of threatened amphibian species, and the Caribbean, where upwards of 80 percent of amphibians are at risk—will be key to the survival of our frogs, toads, salamanders and caecilians. Captive breeding programs in various zoos and labs around the world, reintroductions of species into formerly abandoned habitats, and the removal of harmful non-native species also need to play a role in preserving these many species that, once gone, will never reappear.

CONTACTS: Amphibian Ark; AmphibiaWeb; International Union for the Co

nservation of Nature (IUCN); Conservation International; NatureServe.

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