How seriously have our oceans been polluted with acids?

Dear EarthTalk: I was horrified to read recently that our oceans are actually becoming acidic, that the continued burning of fossil fuels is changing the chemistry of our seas. What’s going on?Kim RichardsonSan Diego, Calif.It’s a known fact that our oceans are becoming more acidic as a result of the increasingly large load of human-generated carbon dioxide (CO2) entering our atmosphere. About 25 percent of all the CO2 we send skyward out of our tailpipes and smokestacks ends up in the world’s oceans, where it triggers chemical reactions in the water column that lead to increased acidification. Researchers estimate that the acidity of our seas has increased 29 percent since the dawn of the Industrial Revolution. If we do not slow down the pace of greenhouse gas emissions, our oceans could be two to three times as acidic in 2100 as they already are today, which could prove disastrous to marine ecosystems and the world’s food chain.“When carbon dioxide is absorbed by seawater, chemical reactions occur that reduce seawater pH, carbonate ion concentration and saturation states of biologically important calcium carbonate minerals,” reports the National Oceanic and Atmospheric Administration (NOAA). These calcium carbonate minerals, typically abundant in areas where most marine life congregates, are the building blocks for the skeletons and shells of many marine organisms, from oysters to coral. “However, continued ocean acidification is causing many parts of the ocean to become undersaturated with these minerals, which is likely to affect the ability of some organisms to produce and maintain their shells,” adds NOAA. The process will not only wreak havoc on the shellfish we eat, but also on smaller marine organisms that are key components on the lower end of the marine food chain.According to the Natural Resources Defense Council (NRDC), a leading green group, coral reefs around the world may face an even greater risk than shellfish because they require very high levels of carbonate to build their skeletons. “Acidity slows reef-building, which could lower the resiliency of corals and lead to their erosion and eventual extinction,” they write. This would be an unmitigated environmental disaster, given that an estimated one million marine species depend on healthy coral reefs for survival.“Such losses would reverberate throughout the marine environment and have profound social impacts, as well — especially on the fishing and tourism industries,” NRDC reports. “The loss of coral reefs would also reduce the protection that they offer coastal communities against storms surges and hurricanes — which might become more severe with warmer air and sea surface temperatures due to global warming.”Researchers are working on strategies to protect aquaculture farms from further losses due to acidic water, but any large-scale effort to address ocean acidification will require the slowing down or phasing out of fossil fuels. Powering our cars, heating our homes and running our machines and appliances all require burning fossil fuels which generate greenhouse gas emissions and in turn cause acidification. Cutting back on our consumption of oil, gas and coal and switching to renewable energy sources — solar, wind, biomass and others — will be a necessary part of the strategy to counteract ocean acidification.We can all help by driving less and walking/biking more; upgrading our vehicles, light bulbs and appliances to more energy efficient versions; patronizing companies that work to reduce their carbon footprints; and pushing our state and federal governments to enact binding reductions in CO2 pollution.Contacts: NOAA, www.noaa.gov; NRDC, www.nrdc.org.Dear EarthTalk: Is it true that cable and other pay TV boxes that sit atop television sets consume massive amounts of energy, in part because they are always on, even when the TV is off?Sam WinstonMetarie, La.We hear a lot about how much energy modern day flat screen TV sets consume, but the innocuous set-top boxes that drive them, along with their built-in digital video recorders, may be even more to blame. A recent analysis conducted by the consulting firm Ecos on behalf of the Natural Resources Defense Council (NRDC) found that “the average new cable high-definition digital video recorder (HD-DVR) consumes more than half the energy of an average new refrigerator and more than an average new flat-panel television.” Overall, set-top boxes in the U.S. consume some 27 billion kilowatt-hours of electricity. This is equal to the annual output of six average (500 megawatt) coal-fired power plants and accounts for the emission of 16 million metric tons of carbon dioxide. Part of the reason these boxes are such energy hogs is that they typically operate at nearly full power even during the two-thirds of the time when they are not actively in use driving TV screens or recording to built-in DVRs. “As a nation, we spend $2 billion each year to power these boxes when they are not being actively used,” reports NRDC.To make matters worse, American consumers have little if any choice about which set-top boxes they get from their cable or satellite service providers. Since the providers usually own the boxes yet don’t have to pay consumers’ electric bills, they have little incentive to utilize or develop more efficient models. In Europe, Sky Broadcasting is beginning to distribute more efficient equipment to subscribers there. NRDC is urging the largest pay-TV service providers in the U.S. (Comcast, Time Warner, DirecTV, Dish Network, Verizon and AT&T) to heed the efficiency call with their own set-top box and DVR offerings.Redesigning set-top boxes to power down when not in use is perhaps the biggest opportunity for energy savings. “Innovation to reduce power consumption when not in active use—such as has occurred with mobile phones, which also work on a subscriber basis and require secure connections—is sorely needed in set-top boxes,” counsels NRDC. Also, re-jiggering content delivery systems so that only one main set-top box sends signals to all the televisions in the house (or to lower power “thin client” boxes) could also cut down household electric bills and carbon footprints. The group adds that “better designed pay-TV set-top boxes could reduce the energy use of the installed base of boxes by 30 percent to 50 percent by 2020.”Last year the U.S. government released new energy efficiency standards for set-top boxes within its EnergyStar appliance efficiency rating program. While this new specification is a step in the right direction, consumers have little knowledge about such options. NRDC urges pay-TV subscribers to request that their providers make available set-top boxes and DVRs that meet the newer EnergyStar 4.0 standards. The more of us that request such improvements, the likelier they are to happen. And the cable or satellite provider that can save customers money while reducing overall environmental impact may just win over an increasingly large sector of the American people that actually cares about being green.Contacts: NRDC’s “Better Viewing, Lower Energy Bills, and Less Pollution,” www.nrdc.org/energy/files/settopboxes.pdf; EnergyStar, www.energystar.gov. EarthTalk is written and edited by Roddy Scheer and Doug Moss and is a registered trademark of E - The Environmental Magazine (www.emagazine.com). Send questions to earthtalk@emagazine.com. Subscribe: www.emagazine.com/subscribe.