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Earth A Live: Focus on environment
Recycled Plastic Bridge
You may have heard of plastic bottles being recycled into fleece jackets, park benches, and of course, more plastic bottles — but bridges? Yes, that’s one of the latest creative uses for old milk cartons, soda containers, and the like.
A 56-foot-long, one-lane bridge over the Mullica River in southern New Jersey, built almost entirely of a special, super- strong plastic blend, has held up well for more than a year, and the team of Rutgers University scientists behind the project see a big potential market for small plastic bridges, though they say the technology isn’t yet ready for large, heavily travelled spans, such as those that are part of the interstate highway system.
The New Jersey bridge was erected for just $75,000, compared to the estimated $350,000 that a standard wooden bridge would cost. Plastic bridges are also preferable to wood ones because they don’t need to be treated with chemicals to ward off insects.
Reindeer frozen out by rain
Rainfall in the snowy northern regions of Scandinavia, Canada, and Alaska creates a layer of ice that prevents reindeer, caribou, and elk from foraging. Rainwater pools and freezes between the snowpack and soil, creating a layer of ice that significantly raises the temperature of the soil. The warmth encourages the growth of fungi and mold that the animals avoid. Eventually, many animals starve, disrupting the subsistence herding of indigenous peoples.
The rainfall is part of a naturally occurring weather pattern in the northern hemisphere called the North Atlantic Oscillation (NAO). Changes in air circulation make some winters cold and dry and others warm and wet in a manner similar to El Niqo. But researchers warn that future climate change may tip the balance toward more rain and expand affected areas by as much as 40 per cent. The findings were reported in Nature.
Climate change alters salt levels in Atlantic Ocean
The Atlantic Ocean seems so vast that it’s almost impossible to imagine fundamentally altering it — and yet, its salt levels have changed so drastically over the last 40 years because of global warming that the whole flow of ocean water is being disrupted, according to a study published in the journal Nature.
As the planet warms, more ocean water evaporates than normal, causing the concentration of salt to increase in certain areas and, because the overall salinity of the ocean must remain the same, to decrease in others. Because salty water is heavier than fresh water, these changes alter the way ocean water flows around the planet.
In a kind of vicious climate-change circle, that alteration will have its own dramatic effects on the global climate, changing and redirecting such basic forces as the Gulf Stream, which keeps places like England and Ireland relatively warm and inhabitable, even though they share the same latitude as the far colder southern Alaska. If ocean salinity continues to change, the study found, Northern Europe could become as much as 10 to 20 degrees cooler than it is today.
Exposure to pesticides may lead to childhood asthma
Children exposed to household bug-killing chemicals during the first year of life may be more than twice as likely to develop asthma as those not exposed, according to new research by scientists at the University of Southern California. Kids’ asthma risk is also increased by exposure to wood smoke, cockroaches, and farm animals.
Childhood asthma has hit epidemic proportions in the US, affecting more than 3.5 million kids under the age of 15; nearly twice as many children had asthma in 1999 as did in 1980.
The writer works in Communications for IUCN-The World Conservation Union, Pakistan.
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