By Art DeGaetano, Professor and Associate Chair of the Cornell University Department of Earth and Atmospheric Sciences and Director of the NOAA Northeast Regional Climate Center
It’s November, Election Day, and as I begin to write this article, my meteorology undergraduates inform me that the high today will reach 70°. Although not unheard of, an occurrence that is rare in Ithaca; but one that is becoming increasingly more common. Since 1970, 70° November days have occurred on average every 2-3 years. Prior to this, in a record that extends back to 1893, the wait for a 70° November day was almost twice as long; as such temperatures were reported every 4-5 years. While a single November day in the 70s cannot be blamed on climate change, this is just one of many examples of what might become common in upstate NY in a warmer world.
In recent years, the Department of Earth and Atmospheric Sciences and Northeast Regional Climate Center at Cornell, together with colleagues at Cornell and other universities in the region, have led efforts to assess the how global climate change is already impacting New York and project how the climate of the state and region might look throughout the next century. Our most recent work, funded by the New York State Energy Research and Development Authority (NYSERDA), looked at the expected climate change impacts and opportunities that different regions and economic sectors within New York might experience in the current century and outlined potential strategies that New Yorkers might consider to effectively adapt to climate change. This report, known as ClimAID, is expected to be formally released in late November. Read it HERE. It represents a 3-year effort by faculty, post docs and students at Cornell and colleagues at Columbia University and Hunter College in New York City.
Across Northeastern United States, average temperatures have risen by over 2°F since 1970. Winter temperatures are 4°F warmer. Although total precipitation amounts have only increased slightly in the region, by approximately 3.3 inches over the last 100 years, the Northeast has seen a 67% increase in the number of 2-inch rainfall events since the 1950s. The persistence of winter snow cover has also declined, with some stations in central and northern NY seeing 30 fewer days with snow cover than in the past.
The future holds more of the same. In western New York and the Finger Lakes Region, the ClimAID report indicates average temperatures will increase by 1.5 to 3°F by the 2020s; 3 to 5.5°F by the 2050s; and 4 to 9°F by 2080, depending on the amount of greenhouse gases humans continue to emit into the atmosphere. Total precipitation will also continue to increase by up to 15% by the 2080s. However most of the change in precipitation will occur in winter, with decreased rainfall possible in the summer and fall. The occurrence of temperature and rainfall extremes will also change. By the 2080s, Rochester is expected to experience 14 summer days with temperatures > 95°F as compared to only 1 under current climate conditions. Only about 80 winter days will fall below 32°F as opposed to the more than 130 that are expected in today’s climate. Two-inch rainfall events will be an every year occurrence in 2080, as opposed to every other year as we now expect. Snow cover will also continue to decline by as much as 25 to 50% by the end of the next century.
These changes are expected to have their biggest impacts on water resources, energy demand, agricultural production and ecosystems in the Finger Lakes region. With warmer and drier summer conditions, water demand may exceed the supply of small water systems that rely on stream flow and shallow home wells. Competition for water resources will increase as the need for supplemental irrigation of fruit and vegetable crops will increase. Warmer, less-snowy winters will increase the chances that weed seeds and insects will overwinter, leading to increased disease pressure on agricultural crops and enabling the spread and establishment of invasive species in ecosystems. Cold-temperature dependent plant and animal species such as the spruce forests of the Adirondacks and the state fish, the brook trout, will be adversely affected. Dairy production is also expected to decline, unless dairy operations can increase their cooling capacity. Warmer summer temperatures are expected to increase the demand for air conditioning, perhaps stressing the existing power supply.
On a more positive note, the changing climate will also bring opportunities of which New York should be prepared to take advantage. Longer, warmer growing seasons will allow new crop varieties to be introduced. This might include crops like watermelons and peaches. Warmer winters may allow vineyards to grow less-cold-hardy, higher-value European grape varieties. This could lead to further expansion of the New York wine industry, particularly since more negative impacts will be felt in competing U.S. wine-producing regions. Water resources are also likely to be more abundant than in other parts of the country that have seen increased population growth in recent decades, perhaps leading to population growth in New York and the return of industry to the state.
Recent observed trends in temperature, precipitation and snow cover across the Finger Lakes Regions are harbingers of the changes that will continue through the century. Adapting to these changes will be challenging given the diverse geography, economy and society of the region and state. The interactions of climate change with other issues, such as demographic changes, invasive species, and economic growth and will create new challenges. The ability to meet these challenges will depend upon how well private and public stakeholders develop effective adaptation strategies and are prepared to capitalize on potential opportunities.