November SkepTalk: Climate Change from the Biotic to the Exotic - Minda Berbeco, PhD

November’s SkepTalk provided the perfect opportunity to Minda Berbeco, PhDMinda Berbeco, PhDintroduce to the Bay Area Skeptics the newest member of the NCSE family, Dr. Minda Berbeco.

As their new Programs and Policy Director, Dr. Berbeco works to defend science education in the United States using experience she has culled from a career investigating the effects of climate change on terrestrial systems. Her investigation of the unexpected and unusual effects of climate change on biological organisms was the focus of her talk this month for the BAS.

Dr. Berbeco began her presentation by surveying the audience about their knowledge of the effects of global climate change. Answers included such things as extreme weather, the endangerment of wildlife, a rise in global sea levels, etc. After pointing out how the audience’s feedback suggested a good working knowledge of the effects of global warming, as well as the disparate areas of concern, Dr. Berbeco announced that she would concentrate her talk on a few specific examples through which she hoped to reveal some of the key concerns scientists are attempting to investigate.

One of the most impressive aspects of Dr. Berbeco’s talk was her ability to tie difficult scientific ideas to everyday issues that people might be better able to relate to than mathematical formulas or large charts with temperature readings. Chief among these was her discussion of the effects of global climate change on wine. She began by asking for a volunteer from the audience to taste a glass of red wine and report the flavors she or he experienced. Never one to pass up a free glass of vino, our own David Almandsmith jumped into action. After taking a generous sip, David described the wine in impressively specific ways, including “tartness of persimmons, cinnamon,” and “relatively dry.”

Dr. Berbeco used David’s description to illustrate that many of the aspects of our food that we enjoy the most, wine included, is the result of the climates in which they are grown. Even slight alterations in weather can change these climates in ways that dramatically affect our food’s taste, smell, appearance, and even nutritional value. For vineyard owners, this part of the “terroir” (aspects of where the grapes are grown, such as geology, geography, and climate) can mean the difference between an award-winning crop, and bankruptcy.

As an example, Dr. Berbeco discussed tannins, a diverse group of chemical compounds in wine that can affect color, aging ability, and texture. They cannot be tasted or smelled, but can be “felt” as the tactile experience wine connoisseurs refer to as “dryness.” These decrease significantly in hotter temperatures, and can dramatically affect the consumers’ experience of many wine varieties. Also of concern is the fact that sugars increase as temperatures rise, making formerly mild wines taste sweeter. Perhaps even more alarmingly, some climate changes negate plants’ natural ability to ward off insets, putting entire crops at risk, and increasing the need for chemical pesticides.

Dr. Berbeco went on to explain that the impact of global climate change isn’t limited to flora. Animals are also affected in some pretty dramatic ways, particularly those who live in the ocean. In a short video, she explained that over 30% of the carbon pumped into the atmosphere is absorbed by our oceans, creating a cascade effect that leads to an increase in ocean acidification. Even slight changes in Ph balance can lead to some pretty nasty disadvantages. Sea snails, for instance, use their sense of smell to tell them when predators are in the area, at which point they harden their shells in defense. In a more acidic environment, they can lose this ability, leading to a very happy population of crabs, but a severe increase in the things that sea snails normally eat, including algae, dead fish, etc.

Another example Dr. Berbeco provided was clownfish (yes, the Nemo variety). Scientists have found that they are particularly sensitive to elevated levels of carbon dioxide while in the “settlement-stage larvae” phase of their development . As they float around, deciding on which sea anemone to inhabit, they use odors in the water to decide which real estate to claim. These odors do two things for them. First, it helps them choose an area with fewer predators. And perhaps equally important, it assists them in avoiding any area that is near their parents, thus decreasing the likelihood of incest. In a higher CO2 environment, they lose this ability and actually become attracted to their parents’ scent instead. Aside from the emotional reaction most people have to that little factoid, anyone with a high school level understanding of biology knows what sort of havoc such a change would wreak upon the clownfish gene pool.

In the end, those of us who do our part to increase awareness of global climate change, and who try our best to cut back on activities that contribute to polluting the environment, can also proudly boast that we are helping to secure a future full of good wine, well protected sea snails, and incest-free clownfish. I’ll leave it to the rest of you to dream up the bumper sticker for that one.