Science News Review

Global Warming, Biodiversity and Biofuels

Oct 12 at 5:05pm by Aileen

The dramatic breakup of the northern ice sheet has tended to confirm global warming, and there are other indications that things are worse than we thought. Turns out that North America’s Northernmost Lake is showing signs of climate change too.

An international research team reports that a core sample of lake bed sediment indicates a drastic change in algae and diatom concentrations in the lake over the last 200 years, but not in the 8,000 years prior – when the lake was permanently frozen. This tends to support the hypothesis that human industrialization has contributed to the warming.

Even if we stopped releasing greenhouse gases today we’d still have to deal with the effects of climate change, and this has been a concern for important ecosystems’ stability. Good news is that researchers have discovered Forests of Endangered Tropical Kelp surviving just fine in the deep waters off the Galapagos Islands.

According to the researchers, the discovery demonstrates a surprising resilience for tropical marine systems in response to climate change. Using a computer model designed to predict where kelp forests might survive despite warming waters, student divers explored the tropical reefs where the computer had predicted likely kelp habitat. They found the forests growing at depths from 40 to 200 feet below the surface, in the cool water layer. Their find may get this species of kelp removed from the World Conservation Union’s database of threatened species.

Meanwhile, in our struggle to develop alternatives to fossil fuels that contribute to greenhouse gases, the National Research Council has reported a serious effect of increased ethanol production from corn that may lead to changing policies on what biofuels we as a nation decide to develop.

Increase in Ethanol Production from Corn Could Harm Water Quality outlines how, if projected increases in corn production for conversion to ethanol occur, water quality could be significantly harmed. This has to do with agricultural practices and expansion of farmland for growing fuel crops, particularly into arid and semi-arid regions of the country.

Irrigation could divert water resources for drinking, industry and hydropower, fish habitat and recreation. In dry regions corn typically requires more water than soybeans or cotton. Native grasses and switchgrass are possible alternative choices for ethanol production that do not require massive irrigation or intense chemical additives, or new crops could be bioengineered that are more water efficient.

It’s good to see the NRC evaluating the relative wisdom of any dramatic change in agriculture to accommodate biofuels production, as factory farming practices already pose a significant threat to public health by pollution of land and water, and agriculture accounts for a hefty chunk of our fossil fuels use all by itself. But ethanol may not be the best choice anyway, if future cars used a different kind of engine. It turns out that just such engines are under development.

Focusing on biodiesel instead of ethanol may be a better policy. Trucks, trains, agricultural machinery and ships already run on petro-diesel, and could switch to 20-80 biodiesel blends immediately without altering the existing engines. New engines can be run on 80-20 biodiesel mixtures, thereby cutting the petroleum content by an additional 60%. GM could deploy its new passenger diesel engine for at least half its new cars and light trucks as soon as nationwide biodiesel distribution allows and the factories can be re-tooled. People would surely buy them, if the popularity of hybrids is any indication.

Production of biodiesel is more energy efficient and less polluting all the way down the line than production of ethanol, though new technologies are being developed to make ethanol production more efficient (and from more easily grown crops). Bioengineered oil crops that will grow in semi-arid climates could be deployed on land not suitable for growing food crops without intensive additions and irrigation, and the machinery that plants and harvests them can run on biodiesel. Researchers are also looking at algae as a source of oil for biodiesel.

As we plan for the future and attempt to wean ourselves from our addiction to fossil fuels, it helps to remember that Rudolf Diesel, inventor of the diesel engine, designed it to run on vegetable oil in the first place, though petroleum magnates in the early years of the 20th century ensured that only petroleum-based fuel would be used. 100 years later there is hope that his dream may finally come to fruition.

Popularity: 15% [?]