The Environment: Seemingly Small Changes and Their Lasting Effects
Apr 02, 2015 10:24AM ● Published by Cate Reynolds
Since those early days, education and research have opened entirely new areas of study from which we can all benefit. We now appreciate that every act, small or large, can have an unimaginable impact on the world. A recent finding at the University of Iowa illustrates this point.
Scientific study often starts with imaginative curiosity. That certainly describes the question posed by University of Iowa researchers: Can smoke from fires intensify tornadoes? The somewhat unsettling answer, especially for those living in the Midwest, is yes.
The study, published in the journal Geophysical Research Letters, examined the effects of smoke—resulting from spring agricultural land-clearing fires in Central America—transported across the Gulf of Mexico and encountering tornado conditions already in process in the United States. In particular, they looked at the impact on an historic, severe weather outbreak that occurred during the afternoon and evening of April 27th, 2011. That event produced 122 tornadoes, resulting in 313 deaths across the southeastern United States, and is considered the most severe event of its kind since 1950.
The researchers ran computer simulations based upon data recorded during the event. One type of simulation included smoke and its effect on solar radiation and clouds, while the other omitted smoke. The simulation including the smoke resulted in a lowered cloud base and greater wind shear—exacerbating the tornado conditions. Future studies will focus on gaining a better understanding of the impacts of smoke on near-storm environments and tornado occurrence, intensity, and longevity.
This cautionary tale puts us in mind of the so-called “Butterfly Effect,” a possibly apocryphal take on the Chaos Theory whereby a small change at one place in a complex system can have large effects elsewhere—such as a butterfly flapping its wings in Rio de Janeiro might change the weather in Chicago.
But what happens if the butterfly isn’t there to flap its wings?
Perhaps this scenario is already beginning to play out. The U.S. Fish and Wildlife Service estimates that since 1990, about 970 million monarch butterflies have vanished from North America. Once upon a time, the sight of billions of monarchs on their unique-to-butterflies, two-way migration could be relished throughout the continent. They actually fly south in the winter, some traveling as far as 3,000 miles, and hold spectacular winter gatherings in Mexico and California. According to the USDA Forest Service, because migrating monarchs are concentrated in just a few locations during the winter, they are especially vulnerable to harsh weather and to human activities that disrupt or destroy their habitat. Researchers and citizen scientists estimate that only about 56.5 million monarch remain, representing a decline of more that 80 percent across North America.
According to the Xerces Society for Invertebrate Conservation, a major player in the field of monarch preservation, the primary threats to the monarch butterfly include the loss of milkweed—the key plant that monarch caterpillars need to survive—from agricultural and national areas due to, among other things, the large-scale use of systemic insecticides within the breeding range of the monarch.
Some might ask why spend money and effort to save a butterfly? What could be so important about a butterfly? But here’s one more question: What if the species becomes extinct and then we find out how important they were to mankind? —S.H.