Your Bacon, Egg, and Cheese Sandwiches Have a Hefty Carbon Footprint

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Most people know that eating meat, especially red meat—say, hamburgers—is bad for the environment. Raising enough methane-farting, resource-intensive cows to satisfy our cravings for burgers and steaks produces an outsized carbon footprint that plays a significant role in climate change. But what about your breakfast egg-and-cheese? A new study says you should feel guilty about that, too.

Recent findings reported in the journal Sustainable Production and Consumption examine the carbon footprint of 40 different kinds of sandwiches—from the simple ham and cheese to tuna, BLTs, and breakfast sandwiches—both homemade and pre-packaged. Researchers from the University of Manchester calculated the carbon necessary to produce standard recipes, including the agriculture required for the ingredients, the manufacturing of the packaging materials, the refrigeration required to keep the sandwiches cold, and the waste generated. They sourced their estimates from previous studies on the carbon footprint of producing and transporting ingredients like bread, ham, bacon, lettuce, tomato, and canned tuna as well as the energy cost of manufacturing packaging, transporting materials, and taking waste to the landfill.

They found that of all the sandwiches, those that combined pork (or prawns, because prawn and mayonnaise sandwiches are apparently a popular thing) and cheese are the most carbon-intensive. A bacon, egg, and cheese breakfast sandwich clocked in as the most environmentally taxing sandwich of them all, with a carbon footprint of 1441 grams CO2 equivalent—a measurement of the global warming potential—per sandwich. (The diet of the average meat-eater in the UK produces about 7200 grams CO2 equivalent daily. For comparison, if you drive your car four miles, it emits about 1650 grams CO2, roughly.)

Chicken and tuna sandwiches were slightly less carbon-intensive, but vegetarian sandwiches didn't fare as well as you might think—depending on how much and what type of cheese was involved, they could have carbon footprints as high as some of the meat sandwiches.

The researchers suggest that some improvements to the way sandwiches are produced and sold might decrease their carbon footprint by as much as 50 percent. Reducing the amount of meat, eggs, and cheese used, excluding tomato, lettuce, or mayo, reducing packaging, and other changes could all contribute to shrinking a sandwich's carbon footprint. Unfortunately, here's a limit to how much a sandwich's environmental impact can be reduced. You can't really have a BLT without the B, L, or T.

But if you're making it instead of buying it, you're saving a lot of emissions. As you might expect given the environmental cost of packaging, ready-made commercial sandwiches had a much bigger carbon footprint than their homemade counterparts containing the same ingredients—2.2 times larger, in fact.

Just another reason to feel guilty about not bringing your own lunch from home.

Thick Arctic Sea Ice Near Greenland Has Broken Up for the First Time in History

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The sea off Greenland's northern coast has long been referred to as "the last ice area.” The ice there is so old and thick that scientists believed the shelf would be the last to remain intact in the area in the face of climate change. Now, a new development is challenging that assumption: As The Guardian reports, the strongest sea ice in the Arctic has started to break apart for the first time in recorded history.

The ice above Greenland owed its fortitude up to this point to the Transpolar Drift Stream. Ice from Siberia carried by the current collects on Greenland's coast, condensing to create a sturdy ice pack that's more than 13 feet thick, with ridges exceeding 65 feet in some places. The ice has remained whole at least since scientists started keeping satellite records of it in the 1970s, but an unusually warm and windy year has compromised its integrity.

The breaking sea ice has been documented twice this year—once in February and once in August, both times when temperatures spiked above the averages for the region. The heatwaves weakened the ice and dislodged it from the coast, and warm winds pushed it further from land, creating a patch of open water larger than has ever before been observed in the Arctic. Temperatures will eventually drop back down and the gap will close up, but that won't be enough to reverse the damage. The ice has already been displaced to a spot where it will melt more easily the next time warm weather arrives up north.

Climate scientists are rethinking how global warming might reshape the Arctic. Now that "the last ice area" has started to break up, experts are now saying the true last holdout of the region may be further west. Norwegian Meteorological Institute scientist Thomas Lavergne described the phenomenon as "scary" on Twitter.

Less permanent sea ice means polar bears will have fewer areas for hunting marine mammals, their main food source. New gaps in the ice can also trigger a feedback loop: While white ice reflects the Sun's heat, the dark ocean surface absorbs it, raising temperatures and causing ice to melt faster, feeding a perilous cycle. Arctic ice cover at both poles has been shrinking at a rapid rate in recent decades, with the Larsen C breaking off from Antarctica last summer and forming an iceberg the size of Delaware. Scientists predict that there will be no summer ice present in the Arctic Ocean at all starting some time in the next 10 to 30 years.

[h/t The Guardian]

Why You Should Never Flush Your Contacts Down the Drain

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When a pair of contact lenses reach the end of their short life span, it may be tempting to dump them—and the liquid they’re stored in—down the bathroom sink drain. As The Atlantic points out, though, this is bad for the environment.

However small and thin they may be, contact lenses can contribute to microplastic pollution in waterways when they’re not disposed of properly, according to a new study presented at the recent American Chemical Society national meeting in Boston. The study surveyed contact lens users and non-users, and found that 19 percent of users flush the lenses down the toilet or sink drain instead of placing them in the trash. That translates to about 3 billion contact lenses per year, Rolf Halden, a researcher at Arizona State University and one of the study's authors, told The Atlantic.

Halden said he was inspired to look into the issue out of personal interest—he, too, wears contact lenses—and because he couldn’t find any studies on what happens to lenses after they’re flushed down the drain. Halden and his team discovered that the lenses end up in wastewater, where they can sink to the bottom because they are denser than water. There, they could endanger aquatic life, especially bottom feeders that may ingest the particles.

Researchers also found that microbes in wastewater treatment plant systems can degrade the structure of the lenses themselves and break them into tinier pieces. In the larger environment, those bits could be consumed by every organism in the local food chain. In addition, some of the flushed lenses are turned into a treated sewage sludge that is ultimately used to fertilize crops, so the waste could end up in our soil and affect creatures like earthworms. The extent to which this affects humans' food supply is not currently known.

"Ultimately, we hope that manufacturers will conduct more research on how the lenses impact aquatic life and how fast the lenses degrade in a marine environment,” Halden says in a statement.

So the next time you’re done using your contact lenses, think of the fish and worms, and throw them in the trash instead.

[h/t The Atlantic]

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