Operation Green

Solar Energy at Home

Imagine never paying another electric bill. Solar energy could make this a reality. Solar electric systems employ photovoltaic cells to convert sunlight into electricity, while solar water heaters use solar collector panels to warm up water.

When the sun is out, if households are generating more power than they need, they can put that energy into the electric grid, and even receive credit toward future bills from the local electric company. At night or in cloudy weather, homes can draw energy off the conventional grid. Continue Reading…

Toss Biodegradable Plastics into the Sea

A biodegradable plastic that dissolves into nontoxic components in seawater could make it environmentally safe to ditch “disposable” forks, spoons, wraps and other such waste overboard from ships to free up valuable space.

“There are many groups working on biodegradable plastics, but we’re one of a few working on plastics that degrade in seawater,” said researcher Robson Storey, a polymer scientist at University of Southern Mississippi. “We’re moving toward making plastics more sustainable, especially those that are used at sea.”

Cruise liners, naval warships and other vessels generate huge volumes of plastic trash, such as stretch wrap for large cargo items, food containers and eating utensils. This junk often remains onboard for long spans of time until ships make port. Simply dumping such junk overboard is hazardous because conventional plastics can take years to break down and may result in toxic byproducts.

When exposed to seawater, the new plastics can dissolve in as few as 20 days. They are made of polyurethane modified to incorporate a biodegradable compound known as PLGA, which is used in medical sutures.

Less Pollution on City Sidewalks than Streets

Passengers in taxis, buses, and cars all inhale substantially more pollution than cyclists and pedestrians, a new study shows.

Researchers measured levels of ultrafine, traffic-produced pollution particles on busy London streets using a newly developed particle counter fitted with a video recorder.

The equipment allowed them to match particle levels with each of the five modes of transport. They also could identify what activities and behaviors lead to the highest exposures.

The Results

On average, taxi passengers were exposed to more than 100,000 ultrafine particle counts per cubic centimeter. Bus travelers were exposed to just under 100,000 and people in cars about 40,000.

Pedestrians and bicyclists, meanwhile, were exposed to counts of just 5,000 and 8,000, respectively. Continue Reading…

Permanent Arctic Ice Nearly Gone

Vast sheets of ice up to 260 feet (80 meters) thick have throughout modern history blocked ships seeking a short cut through the fabled Northwest Passage from the Atlantic to the Pacific. But that ice, known as multiyear ice because it has not traditionally melted during summer like seasonal ice does, is nearly history, Reuters reports.

“We are almost out of multiyear sea ice in the Northern Hemisphere,” David Barber, Canada’s Research Chair in Arctic System Science at the University of Manitoba. Barber led a mission searching for multiyear ice and instead found a lot of “rotten ice,” or thin layers that was “easy to navigate through.”

Arctic sea ice has been melting at rapid rates in the last decade. The summer minimum ice area in the Arctic has been far below the 1979-2000 average in recent years.

The Northwest Passage opened in 2007 during a record low for Arctic Ice. Last summer resulted in the second lowest sea-ice extent.

Recent studies have predicted that the Arctic could be essentially ice-free during summer within 30 years, due to a warming planet. Most recently, Peter Wadhams, head of the polar ocean physics group at Britain’s Cambridge University, said: “In about 10 years, the Arctic ice will be considered as open sea.”

There’s Still a Chance to Save Polar Bears

With all the attention given to the loss of sea ice in the Arctic, it’s easy to forget that some ice will persist for many years yet. True, climate models project that much of the Arctic Ocean will be ice-free in summer by 2040, but they also predict that half a million square kilometres of sea ice could remain until at least 2100.

This ice will lie next to the northern coasts of Greenland and the Canadian Arctic archipelago, the region where the oldest and thickest ice now occurs. This region will therefore offer at least a limited sanctuary for species that prefer, or rely on, year-round sea ice. Projections published in February indicate that by the middle of the century optimal polar bear habitat will have disappeared across most of the Arctic, but will persist north of the Canadian Arctic archipelago and Greenland.