The New England states are known for their vibrant autumn colors. Anyone driving through that part of the U.S. when temperatures stop dropping is in for a show of nature. Unfortunately for those who look forward to this fall spectacle every year, a change in the timing of leaf coloration could be added to the list of things disturbed by global rising temperatures.

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The reason the leaves change color in the first place is a lack of chlorophyll. This is brought on by a lack of sunlight and a change in temperature because plants must restrict the flow of water and minerals to their leaves in order to survive the shorter and colder days. Leaves from different plants turn different colors, which is dependent on the pigments that are present in the leaves when the green chlorophyll fades away. Eventually the leaves turn brown and drop off. This dead leaf matter helps to replenish nutrients and minerals into the soil around the plants.

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Higher global temperatures caused by an anthropogenic increase in greenhouse gases impacts many other naturally maintained processes. Global climate change can cause changes in humidity, cloud cover, increases in growing season length, higher levels of certain nutrients in the atmosphere, soils, and waterways, a difference in migration patterns, and changes in competition by invasive species.

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A change in temperature and daylength is already influencing the timing of organisms’ life cycles. For example, the migration patterns of certain birds and insects is shifting due to a different in warmth and therefore food availability. In dealing with the leaf color, they could change at a different time, or most extremely, not at all.

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One of the big questions, according to the Appalachian State University Department of Biology, is how global climate change is going to affect tree distribution. Trees have already migrated further north and higher in elevation due to increased temperatures. These species are not only moving further up, but they are also leaving the places where they once lived because it is too warm. The sugar maple, a dominant species in the northeast, is expected to move north into Canada. This has consequences as far as viewing fall colors goes, but the New England states are also known for their maple syrup products, so a lack of sugar maples would destroy that market in areas where the tree can no longer survive.

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Invasive species are already devastating ecosystems, but increased temperatures are allowing them to cover more geography. This includes many different organisms, including dangerous diseases. Many organisms are kept at bay by the harsh winters of the north, which also cause a change in leaf color.

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The Appalachian State University of Biology noted that a change in fall foliage is hardly the biggest concern related to global climate change. There has already been concerns over water and food scarcity and rising sea levels. The general consensus is that global climate change is predicted to have far more negative effects than beneficial ones, and that less beautiful fall foliage should be another motivator in reducing fossil fuel emissions.