Winter is almost over, but for some parts of the United States, it felt like it never really arrived. The National Oceanic and Atmospheric Administration has confirmed that this winter was the warmest ever on record for the country. This winter has been unprecedented in terms of its warmth, with many cities ranking in the top 10, top 5, or even experiencing their warmest winter on record.
The upper Midwest and Northeast regions saw a significant number of cities experiencing their warmest winter on record, as indicated by the abundance of red dots on the map. Eight states, including all cities within those states, hit their warmest winter on record statewide, marking a remarkable weather phenomenon.
Overall, this winter was five degrees above average, with 26 states ranking in the top 10 warmest. February specifically experienced a 7-degree fever, ranking as the third warmest on record. This warmth led to record low levels of ice on the Great Lakes, dropping to just 2% in February.
The presence of El Nino, a warm ocean circulation in the Pacific, contributed to the expectation of a warm winter. However, the record heat was also influenced by climate change, making such extreme weather events more likely. The impact of climate change was evident in the number of days with very warm winter air, particularly in the upper Midwest.
While a cold snap did occur in January, it was made four to five times less likely by climate change. The frequency and intensity of cold snaps have decreased since 1970, with warmer winter days becoming more common across the U.S.
The implications of such a warm winter are significant. Early insect activity, increased disease transmission, an earlier allergy season, and a premature start to the growing season can all have adverse effects on agriculture. Additionally, reduced snowfall poses challenges for ski resorts and water reservoirs, impacting businesses and water supply.
As we reflect on the unusual weather patterns of this winter, it becomes clear that the intersection of natural climate phenomena and human-induced climate change is reshaping our seasons and ecosystems in profound ways.