Climate Change Affecting Autumn's Colors
2021-10-06
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1Leaf peeping is a beloved yearly activity in many parts of the world, including parts of the United States.
2The northeastern and mid-Atlantic states are especially popular for beautiful fall colors.
3Leaf peeping is when people travel to see the beautiful colors of fall foliage.
4Foliage is another name for leaves, and fall is another word for autumn.
5However, recent fall leaf peeping seasons have been changed by weather conditions.
6A lack of rain causes leaves to turn brown and die before they can reach the best color.
7Heat waves cause leaves to fall before autumn even arrives.
8And extreme weather events, like hurricanes, take the leaves off trees altogether.
9Climate change also creates longer-term threats that could harm leaf peeping.
10The spread of diseases and insects is also tied to warming temperatures.
11These are all affecting autumns famous fall colors.
12Scientists say that this is likely to continue as the planet warms.
13Some of these scientists recently spoke with The Associated Press.
14Typically, by the end of September, some leaves turn colors throughout the U.S.
15 However this year, trees in many areas are still green.
16For example, in northern Maine, the best time for leaf colors usually happens in late September.
17But on September 29, Maine forest officials had reported less than 70 percent color change of the leaves and only moderate leaf drop.
18Across the country in Denver, Colorado, high temperatures have left "dead, dry edges of leaves" early in the season, said Michael Sundberg.
19He is a tree expert in the area.
20 Sundberg told the AP that instead of slow change, trees are affected by abnormal weather.
21"They change all of a sudden, or they drop leaves early," Sundberg said.
22"Its been a few years since we've had a really good leaf year ..."
23The reason climate change can be bad for fall leaves has to do with plant biology.
24When fall arrives, days lengthen and temperatures drop.
25The chlorophyll in a leaf breaks down.
26And that causes the leaf to lose its green color.
27The green leaf turns into a beautiful yellow, red or orange autumn leaf.
28Getting those beautiful colors requires a balance, said Paul Schaberg.
29He is a research plant physiologist with the U.S. Forest Service based in Burlington, Vermont.
30Warm fall temperatures, he said, can cause leaves to remain green longer.
31Worse than that, Schaberg said, very dry summers can stress trees and cause their leaves to miss the fall colors completely.
32A 2003 study in the journal Tree Physiology that Schaberg co-wrote stated that "environmental stress" can speed up leaf decay.
33He said in severe droughts trees experience difficulty.
34That is happening already.
35This summer's heatwave in the Pacific Northwest of the U.S. led to a condition called "foliage scorch."
36Foliage scorch is when leaves brown too early, explained Chris Still.
37He is a professor at the Forest Ecosystems & Society department at Oregon State University.
38In some parts of Oregon, leaves lost their color early and then quickly fell to the ground.
39This led to a shorter and less beautiful leaf peeping season.
40"That's a really big example of color change just due to heatwave shock," Still said.
41The economic impact of poor leaf peeping seasons could also be significant.
42Officials throughout New England have said fall tourism brings billions of dollars into those states every year.
43Conservationists say that is one good reason to work to preserve forests and reduce the use of fossil fuels.
44I'm Anna Matteo.
1Leaf peeping is a beloved yearly activity in many parts of the world, including parts of the United States. The northeastern and mid-Atlantic states are especially popular for beautiful fall colors. 2Leaf peeping is when people travel to see the beautiful colors of fall foliage. Foliage is another name for leaves, and fall is another word for autumn. 3However, recent fall leaf peeping seasons have been changed by weather conditions. 4A lack of rain causes leaves to turn brown and die before they can reach the best color. Heat waves cause leaves to fall before autumn even arrives. And extreme weather events, like hurricanes, take the leaves off trees altogether. 5Climate change also creates longer-term threats that could harm leaf peeping. The spread of diseases and insects is also tied to warming temperatures. These are all affecting autumns famous fall colors. 6Scientists say that this is likely to continue as the planet warms. Some of these scientists recently spoke with The Associated Press. 7Typically, by the end of September, some leaves turn colors throughout the U.S. However this year, trees in many areas are still green. 8For example, in northern Maine, the best time for leaf colors usually happens in late September. But on September 29, Maine forest officials had reported less than 70 percent color change of the leaves and only moderate leaf drop. 9Across the country in Denver, Colorado, high temperatures have left "dead, dry edges of leaves" early in the season, said Michael Sundberg. He is a tree expert in the area. Sundberg told the AP that instead of slow change, trees are affected by abnormal weather. 10"They change all of a sudden, or they drop leaves early," Sundberg said. "Its been a few years since we've had a really good leaf year ..." 11The reason climate change can be bad for fall leaves has to do with plant biology. When fall arrives, days lengthen and temperatures drop. The chlorophyll in a leaf breaks down. And that causes the leaf to lose its green color. The green leaf turns into a beautiful yellow, red or orange autumn leaf. 12Getting those beautiful colors requires a balance, said Paul Schaberg. He is a research plant physiologist with the U.S. Forest Service based in Burlington, Vermont. Warm fall temperatures, he said, can cause leaves to remain green longer. 13Worse than that, Schaberg said, very dry summers can stress trees and cause their leaves to miss the fall colors completely. A 2003 study in the journal Tree Physiology that Schaberg co-wrote stated that "environmental stress" can speed up leaf decay. 14He said in severe droughts trees experience difficulty. 15That is happening already. 16This summer's heatwave in the Pacific Northwest of the U.S. led to a condition called "foliage scorch." 17Foliage scorch is when leaves brown too early, explained Chris Still. He is a professor at the Forest Ecosystems & Society department at Oregon State University. In some parts of Oregon, leaves lost their color early and then quickly fell to the ground. This led to a shorter and less beautiful leaf peeping season. 18"That's a really big example of color change just due to heatwave shock," Still said. 19The economic impact of poor leaf peeping seasons could also be significant. Officials throughout New England have said fall tourism brings billions of dollars into those states every year. 20Conservationists say that is one good reason to work to preserve forests and reduce the use of fossil fuels. 21I'm Anna Matteo. 22Patrick Whittle reported this story from Maine for the Assoicated Press. Anna Matteo adapted this story for VOA Learning English. was the editor. 23______________________________________________________ 24Words in This Story 25hurricane - n. a tropical cyclone with winds of 74 miles (119 kilometers) per hour or greater usually accompanied by rain, thunder, and lightning 26chlorophyll - n. the green substance in plants that makes it possible for them to make food from carbon dioxide and water 27physiologist - n. a person specializing in the biological study of the functions and processes of living organisms and their parts 28stress - n. a force that tends to change the shape of an object 29decay - v. to undergo decomposition 30drought - n. a period of dryness especially when prolonged 31scorch - v. to burn a surface of so as to change its color and texture 32significant - adj. large enough to be noticed or have an effect 33conservationist - n. someone who works to protect animals, plants, and natural resources or to prevent the loss or waste of natural resources : a person who is involved in conservation