The growing seasons are shifting. Spring is arriving earlier, winters are shorter, and the number of freezing days is declining. These changes affect the timing of many lifecycle events, such as when flowers bloom or when pollinators emerge. Changes in the timing of these events — spring thaw or songbird migration, for example — can have adverse effects on ecosystems, because different species may respond to different environmental cues, resulting in a misalignment between species that may rely on one another.
Why Are Seasons Shifting?
Shifting seasons are directly linked to warmer global temperatures. A slight change in temperature is enough to push the spring thaw earlier, and delay the first frost until later in the fall. These environmental changes cause many trees and spring wildflowers to bloom earlier than typical. As a result, winters are shorter, spring is earlier, summers are longer and fall arrives later.
How do shifting seasons affect natural resources and conservation priorities?
The consequences of shifting seasons include:
- Potential misalignment between lifecycle events of species that rely on one another.
- Greater risk of frost damage. The earlier arrival of warm temperatures may cause many trees and flowers to blossom earlier, however, the risk of frost lingers. Since some plants are highly vulnerable to frost damage, this can significantly impact the fruit, nut, or seed production of frost-affected plants.
- Increased risk of drought, due to the earlier timing of snow-melt and the longer duration of summer.
- Planting zones are shifting further north.
- Pests and diseases may have a greater impact, because they will begin feeding and breeding earlier in the season. Some pest species will also increase in numbers due to milder winters, which allow more individuals to survive until spring.
Shifting seasons are also a trigger for other climate change impacts, such as: