New York leaf-peeking: Will peeping leaves be affected by climate? - Democrat & Chronicle

New York leaf-peeking: Will peeping leaves be affected by climate?

Will climate change hurt the fall leaf-peeking in Upstate New York and Rochester in 2023?
William Ramsey

- As peak leaf-peeping season spreads across the U.S. each fall, it brings billions of dollars in tourism to some states, according to Climate Central.
- The timing and brilliance of fall color are influenced by temperature, sun exposure, and rainfall—along with a range of other conditions.
- These conditions are shifting with climate change, disrupting the ecological and economic value linked to fall foliage.

Will climate change affect the leaf-peeping display in Upstate New York this year?

Yes.

Global warming has changed weather patterns and introduced an incremental year-over-year and decade-over-decade rise in average temperature.

"Over the last century, average winter temperatures have increased by approximately 3°F, spring temperatures by 2°F, and summer and fall temperatures by 1.4°F," according to the New York State department of environmental conservation.

In New York, the first signs of fall foliage are appearing in the Adirondacks, Catskills, Thousand Islands-Seaway and Chautauqua-Allegheny, according to field reports from observers for the tourism I LOVE NY program.

“In general, summers with lots of sunny days and adequate moisture are probably the ideal conditions for vibrant foliage,” said the director of Cornell’s Northeast Regional Climate Center, Art DeGaetano, in a statement. “This summer lived up to these conditions in some places, especially northern New England.”

What are conditions for fall leaf-peeping in Upstate New York, Rochester?

According to the National Weather Service —

WARMER AND DRIER ROCHESTER: "During the meteorological summer (June 1st through August 31st) of 2023, Rochester was warmer (70°F of +1.3°F and much drier than normal. A total of 5.03" of rain fell. This was 8.63" drier than normal or 4th driest. During meteorological summer, Rochester International Airport had an average temperature of 70°F."

In New York, this is the best time this fall for seeing leaves, according to the Farmer's Almanac:

— Sept. 28-Oct. 28, depending on elevation and distance from the coast.

What changes how colorful the fall foliage season is?

The key resource for journalists on climate change called Climate Central explains a few key factors that affect what kind of beautiful autumn portrait you will see outside your kitchen window:

- " Temperature: Fall temperatures have increased by 2.7 °F on average across the U.S. since 1970, delaying the cool trigger that plants need to start shutting down. Warmer autumn temperatures generally (though not always) lead to later and shorter peak fall foliage periods.
Sun exposure: As fall days shorten, the reduced sun exposure cues plants to ramp down photosynthesis. This process reshuffles leaf pigments and starts the colorful displays of fall. When tree species shift northward in response to warming, shorter days at higher latitudes can cause earlier leaf color and drop.
Rainfall: Abundant summer rain and soil moisture can cause later, brighter color. But too little or too much rain can both stress trees and cause leaves to change and drop early," according to Climate Central.

The colors themsleves of fall leaves are adjusted by climate conditions

Climate Central explains that less time in the sunlight and days that last less long prompt plants to curb photosynthesis for the season. "Doing so reduces chlorophyll (a green pigment used during photosynthesis), revealing orange and yellow leaf pigments that were previously masked by green," their fall report explains. "At this stage, some species (such as red maples) start producing red or purple pigments, enhancing the vibrance of fall forests."

What the thermometer says, how much rain we've gotten and the strength of daylight sun works its magic on leaves. According to Climate Central:

- " Bright and cold days can intensify the production of red pigments.
Cool nights and bright, sunny days can further enhance vivid color displays, which favor a 9-12°F difference between daytime and nighttime temperatures.
Early frost can damage leaves and limit production of red pigments."

Information for this article was contributed by reporting from Camille Fine, Jacob Mack, Victoria Freile and Janet Loehrke.

Where are the best fall colors? Map out best dates and locations for 2023 leaf-peeping

The Democrat & Chronicle has been investigating the effects of a rapidly heating planet on people who live in our city. Follow along with "City on Fire" as we report the struggle with summer temperatures caused by climate crisis. This is part of the USA TODAY project Perilous Course. Check out the podcast by D&C journalist Rob Bell or contact William Ramsey for general climate impact story ideas.