You Should Know

You Should Know

The Dangers of Warm Winters

The Dangers of Warm Winters

by Marcus Glassman

by Marcus Glassman
While Chicagoans may have enjoyed one of the warmest winters on record, the early spring-like weather has real, negative consequences for agriculture and ecology. Here’s what you should know about the dangers of increasingly warmer winters.
While Chicagoans may have enjoyed one of the warmest winters on record, the early spring-like weather has real, negative consequences for agriculture and ecology. Here’s what you should know about the dangers of increasingly warmer winters.
Photo: REUTERS/Dominic Ebenbichler
Photo: REUTERS/Dominic Ebenbichler
In 2017, Chicago experienced its first snowless January and February since records began 146 years ago.
Photo: PIXABAY
In February, Chicago broke records reaching 70 degrees farenheit, Oklahoma hit 99 degrees farenheit, Washington DC’s cherry blossoms began to bloom six weeks early, and California’s unseasonable rains threatened landslides and compromised dams.
Photo: REUTERS/Jonathan Ernst
This "premature spring" coaxed plants out of winter dormancy, making them vulnerable to damage from frost when typical winter weather returns, as it did in the Midwest and Northeast on March 13.
Photo: REUTERS/Jim Young
A late-season cold snap like the one we just experienced can cause largescale losses for crops such as apples, cherries, and peaches—even hardy grains, like winter wheat, aren’t immune from late-frost damage.
Photo: REUTERS/Stefan Wermuth
Michigan apple and cherry crops experienced their worst season in half a century when early spring-like weather was followed by a late frost in 2012.
Photo: iSTOCK
Many plants need a lengthy dormancy to store energy necessary to bloom. An early start means less reserve energy, fewer blooms, and smaller harvests.
Photo: PIXABAY
Plants that come out of dormancy too early and bloom before their pollinators, such as bees, are out of hibernation threaten the success of the year’s harvest.
Photo: REUTERS/Jamal Saidi
Warmer winters also increase the risks from pests and disease. Long, freezing winters often stop the expansion of bacteria, invasive insects, and weeds.
Photo: REUTERS/Juan Carlos Ulate
In the Rocky Mountains, gradually warming winters have aided the rapid expansion of the mountain pine beetle. Today, 1 in 14 trees in Colorado are dead in large part due to this invasive pest.
Photo: REUTERS
Warm winters also can lead to more ticks and mosquitoes. Summer 2017 likely will be particularly bad, and we may see an uptick in the diseases they carry: Lyme disease, West Nile Virus, and others.
REUTERS/Mike Blake

Greater numbers of pests may lead to more aggressive pest-control strategies, potentially increasing the use of herbicides and pesticides on fields and exacerbating already-prevalent issues like herbicide-resistant weeds.

Photo: REUTERS/Ilya Naymushin

The winter of 2017 is one of the warmest on record, but winters have become less and less cold since the 1960s, and the impact on agriculture, pests, and the environment over the past 50 years has been significant.

REUTERS/Brian Snyder

How has your region been affected by this year’s warm winter? Share your experiences with us on Facebook and Twitter at @GlobalAgDev.

©2017 Chicago Council on Global Affairs