WHERE TREE MEETS TUNDRA— EFFECTS OF CLIMATE CHANGE IN THE ARCTIC TUNDRA
If you’re a follower of our blog, then there’s a good chance that you have heard us talking about the Lunch and Learn programming that is made available to individuals who make a substantial financial contribution to the California Science Center. If you’re new to our blog, then we’d like to introduce Lunch and Learn as an expert-led lecture that covers topics such as the Cassini mission to Saturn, humans and their primate ancestors, canine companions, and other science-based topics. This past week, HWF directors, Alex Havasi and Marilyn Fordney, visited the science center and attended a fascinating talk given by Glen MacDonald, Ph.D. a UCLA Professor and the Director of the White Mountain Research Center, who has spent over 30 years researching and writing about the causes of climate change and its impact on society. On this particular visit, guests of the California Science Center listened as Dr. MacDonald described his work among the northernmost limit of trees in the Arctic Circle that border the desolate lands of the Arctic tundra.
Just beyond the northernmost treeline of our world, the Arctic tundra offers an icy landscape stretching for thousands of miles. Spanning across northern Alaska, Canada, and Siberia, the plants and animals living in the Arctic tundra face one of the Earth’s coldest, and harshest climates. Surprisingly, 1,700 types of plants and a handful of mammals such as caribou, arctic foxes, hares, squirrels, and polar bears have evolved to thrive in such a bleak environment. The adaptable flora and fauna that call the barren lands of the arctic tundra home are highly vulnerable to changes in climate. As global temperatures rise, the far north environments appear to be undergoing a transition and food sources are becoming more scarce.
Depending on your location within the expansive tundra, the sun can remain below the horizon for up to 2 months, shrouding parts of the region in complete darkness. Temperatures in the tundra can dip below -30 degrees Fahrenheit, leaving a cutting chill that keeps the grounds covered in permafrost for most of the year. Permafrost is an impenetrable layer of frozen soil, plant life, bones, and ice that have been formed over thousands of years. During the summer months, some regions in the Arctic are exposed to sunlight 24 hours a day. Over this period of time, temperatures in the southernmost regions, peak at 10-20 degrees Fahrenheit and the surface layer above the permafrost begins to melt. These exposed waters invite an explosion of animal life. Insects swarm around the melted pools of ice water, and millions of migrating birds come to feed on them.
In the Arctic, huge forests cover areas of seasonally frozen ground. The treeline is the perimeter of the southern arctic which separates the tundra from the forest and demarks the region in which trees stop growing. Respected researcher, Dr. Glen MacDonald, and his graduate students have devoted many hours to familiarize themselves with the minute changes in the treeline. These tiny changes are of great importance when one considers that trees grow very slowly in the tundra. So slowly, that a 15-year-old tree will measure just 2 feet tall! The coniferous pine and spruce trees growing at the treeline survive frozen winters by conserving water in the limited surface area of their needles. Their roots are stabilized by seasonal permafrost which concerns botanists who fear that increased global temperatures will continue to shrink permafrost zones. MacDonald and other treeline researchers regularly visit the tundra to measure the small growths and to quantify the ways in which climate change has affected this microenvironment.
Climate Change and Carbon Release
Scientists believe that we could see a 50% decline in permafrost over the next century. A harrowing estimate, when you consider that these ancient frozen soils house more carbon than has ever been released from the burning of fossil fuels. As the planet continues to warm, permafrost thaws, releasing carbon dioxide and methane— two powerful greenhouse gasses—into the atmosphere, and accelerating climate change. This increase in carbon contributes to changes in weather patterns, sea level rise, and agricultural production that could have cataclysmic effects on global human populations.
Fire, also poses a threat to the open expanse of tundra and forest in the north. In 2011, the tundra experienced its first wildfire in 10,000-years, a fire that released more than 2.1 million metric tons of soil-bound carbon into the atmosphere.
As we face the realities of a warming planet and witness wildfires spreading at endemic levels across our globe, it is time to ask ourselves what we can do to reshape the effects of climate change. You can start by limiting the level of pollution that you create— carpool, ride your bike, buy electric, and recycle and compost your waste. It is a daunting task to take on climate change, but every effort helps!
A special thanks to Dr. MacDonald for sharing his knowledge and expertise and to Alyson Goodall, Abel Contreraz, and their staff at the California Science Center for arranging such a wonderful educational and informative event.