As we conclude another month of unusual weather in my hometown (Buffalo, NY), I thought it would be a good time to take a look how climate change can be measured locally. Coming off the heels of the coldest month in Buffalo history in February, May featured an average temperature 5.70 F warmer than normal including nine days over 80 degrees. This month was on pace to be the 5th driest May in Buffalo history, but 2 1/2 inches of rain on May 31st more than doubled the precipitation experienced the first thirty days of the month.
Although our lives revolve around daily fluctuations in weather, the best way to determine how global warming may influence local climate is to examine annual temperature as that measure smooths out noise and gives a good take at long-term trends. The global temperature history is below:
A few key trends to notice, the post World War II cooling likely was a result of the global economy recovering after the Great Depression. An increase in atmospheric aerosols caused by industrial emissions blocked sunlight during that period. This helped to offset greenhouse gas heating. Aerosols are particles suspended in the atmosphere rather then a gas such as carbon dioxide.
That era ended with environmental regulations put into effect during the 1970’s. The drop in aerosols prompted global temperatures to rise after 1980. A slight cooling trend took place in the early 1990’s, this was precipitated by the Mt. Pinatubo eruption in 1991. Large volcanic eruptions can eject sulfuric aerosols into the stratosphere and cause global cooling on a scale of 2-3 years. The most famous example of this was the Year Without a Summer in 1816 produced by the eruption of Mt. Tambora. After that brief period of cooling, global temperatures began to march upwards again. This period included the 1998 El Nino warming spike, and the nine of the ten warmest years on record that have occurred after 2000.
So how does Buffalo match up to all this? Lets take a look below:
We have a replication in the progression of temperature change. The post World War II cooling can clearly be seen from the 1950’s through 1979. The 1970’s saw the most infamous weather event in Buffalo history with the Blizzard of ’77. Temperatures begin to warm up after 1980 just as happened globally. The short term cooling effect from Mt. Pinatubo is clearly observed in the early 90’s (the summer of 1992 was very cool and wet) along with the (then) record breaking warmth from the 1998 El Nino event.
Despite the noise from short term climate forcings, the warming trend from 1980 to the current is plainly visible. From 1940 to 1989, only two years clocked in at over 50 degrees. The period from 1990 to 2014 featured six such years including 2012 which shattered the 1998 record by 1.20 F. That might not seem like a lot, but the prior record was only 3 degrees above normal. In other words, if climate models are correct and temperatures increase by more than 4 degrees, the average year will be hotter than the hottest year on record in Buffalo.
What I found really interesting is the greater variation of annual temperatures after 1990 as the yearly figures fluctuate widely across the moving average. Also, even though the winter of 2014 was very cold in its own right, the temperature for the year was still greater than many years during the 1970’s. The trend has been clearly increasing temperatures the past three decades. Is this widening fluctuation in temperatures due to greenhouse gas induced climate change? The answer is uncertain and as many a science article has concluded, more research needs to be done in this area.
What we do know is that we have to prepare to protect our regional economy against the influence of climate change. Decreasing lake waters will make hydroelectricity production more expensive and lower cargo capacity of lake freighters. General Mills, a major local employer (whose plant spreads the aroma of Cheerios downtown), has recognized the dangers of climate change to its supply chain and has a formal policy to mitigate its role in releasing greenhouse gases. The next decade will be key in slowing climate change and will require crucial policy choices at both a regional and national level.
*Image on top of post is Buffalo from Sturgeon Point 15 miles south on Lake Erie. Just wanted to demonstrate it does not snow here 12 months out of the year.