The first time I grasped the impact of climate change on the world of science I was looking at CAT scans of coral. Coming from a physicist, that probably sounds bizarre. In Summer 2011, I had the great privilege of working on a research project at Woods Hole Oceanographic Institution (WHOI – which the summer students pronounced “hoo-ey!” with appropriately nerdy levels of enthusiasm). I spent my summer writing a computer tool to extract density of coral from CAT scan images, in which the intensity (or darkness of the gray color) depends on the density of the material. A less dense material will appear a lighter shade of gray than a more dense material. Coral “grow” every year by depositing calcium carbonate, and the calcium carbonate deposited in the summer is less dense than that deposited in the winter (i.e., they grow more in the summer). The exact density actually correlates strongly to the temperature of the sea near its surface, called the sea surface temperatures, and, thus, we can track the temperature of the oceans over the lifetimes of the coral. Coral can be hundreds of years old, which means that we have temperature records back to before the Industrial Revolution! The sea surface temperatures shows a slow, steady increase since the Industrial Revolution and is convincing evidence that global warming is due to human activity.
Interacting with the scientists at WHOI, I felt a profound sense of sadness and of urgency that we mitigate and possibly reverse global warming. I watched presentations by biologists who displayed pictures of bleached coral and explained how rising SSTs were partly responsible. When the water becomes too warm, the symbiotic algae living on the coral are expelled, leaving the coral white; shown below is a fire coral in Bermuda before and after it bleached.
Similarly, the image at the top of this post shows the same reef in American Samoa in December 2014 on the left while the reef was healthy and in February 2015 on the right when nearly all the coral had bleached. If the coral is too long without the algae, the coral dies. This is a real. This is a problem, I thought. Among those who work in science, it is obvious that climate change is man-made, and many scientists throw themselves into research to find solutions with renewed vigor when global warming is mentioned.
Oceanographic research was not the interest that led me to graduate school, but it came to the forefront of my attention last week. While preparing samples, I was listening to NPR’s Morning Edition and listened to a story about an anthrax outbreak in remote Siberia. Anthrax is a bacterium that naturally lives in the soil and can be deadly if untreated in humans; many who grew up in the United States may remember when in 2001, anthrax was sent through the mail, ultimately sickening 22 people and killing 5. Currently in Siberia, Russian authorities are dealing with an outbreak of this disease, which has so far claimed the life of one child, and prompted the evacuation of several families. The potential source of the outbreak – a reindeer carcass that had been frozen in the permafrost, the (until recently) “permanently frozen layer [of soil] at variable depth below the surface in frigid regions of a planet (as earth” according to Merriam Webster. The hypothesis is that the reindeer died decades ago from an anthrax infection, and its body was frozen into the permafrost. Anthrax survives at such cold temperatures in spores. Because of the higher temperatures this summer, more permafrost than normal melted, and the reindeer’s carcass was exposed. The anthrax spores, when picked up by more reindeer or the people who handled those animals, were activated, and the anthrax multiplied in its new host. The scary implication of this story is that anthrax is just the beginning. Other animals long frozen in the permafrost could be thawed and spread other nasty diseases like Spanish flu, smallpox, or bubonic plague.
If you’re as surprised and dismayed as I am and was, we’re not alone. Most Americans apparently do not grasp the impact of global warming on human health. Even more frightening is that fact that climate change disproportionately hurts those who are already often disadvantaged: women, children, the elderly, low-income countries, indigenous people, etc.
Climate change is not just an issue for science. It is an issue for those pursuing social justice. It affects the supply of the food we eat, availability of the water we drink, and the number of diseases we are exposed to. Scientists alone cannot fix it. Rather, scientists need to educate the public about the causes of and different potential ways to mitigate climate change and to push for policy changes. “Ordinary” people, however, will be the superheroes here because they will make the changes to their lives and push their representatives to pass and uphold climate change legislation.
So how can you be a superhero? Check out the EPA’s website on this topic. If you live in an apartment or house near the University of Minnesota, look into signing up for composting/organic recycling to reduce your landfill contribution. Get on your bike rather than in your car; you can find a map of bike routes in Minneapolis here or use the bike option in Google maps. Most of all, try to spread the word.