The general perception has been that this month has been exceptionally rainy. Since 1881, Fargo Moorhead has averaged 11 days with measurable precipitation during the month of June. In the past 20 years during our current wet cycle, the average has been 12 such days. So far this month, we have recorded 13 days with measurable rain, which is near the long term average with no additional rain foreseen through Wednesday.
June is climatologically the wettest month of the year with average rainfall of 3.51 inches. Hector Int’l has recorded 4.26 inches this month, above average, but not exceptionally so. Hector Int’l as well as a narrow strip of West Fargo got hit with the heavy rain event on June 17 that missed much of Fargo and Moorhead. Areas that got missed recorded 1 to 1.5 inches less rainfall during the month. Our cooperative observer in Moorhead has reported 3.00 inches this month and the WDAY studios 3.11 inches.
This time of year our thoughts are on warm temperatures and thunderstorms, not snow, but to a climatologist the snow season officially comes to an end on June 30. Whereas most weather statistics are kept for the traditional calendar year, winter statistics are measured from July 1 to June 30. The official 2009-2010 winter snow total was 46.6 inches, which by coincidence is exactly at our current 30 year average of 46.6 inches.
Our long-term average since snow record began in the late 1800s is 40 inches. In a climate where our averages are calculated based on extremes it was an odd statistical fluke that we would finish with such a snow total. Although the winter started very snowy, with 24.4 inches falling in December, only a few tenths fell after February 8. You may remember that the weather did not necessarily turn dry after that, but instead the precipitation fell as rain instead of snow.
Summer is the time of year when many of us have time to read a few good books. I was recently asked for recommendations on some easy reading weather related books and I thought I would share the list here as well. These books deal more with how weather has impacted people in the past more than the technical details of how the weather works which makes for much easier reading.
I just finished a book given to me by a co-worker called “Americans and Their Weather” by William B Meyer which deals with roles played by weather and climate in American life. One of my favorite historical weather books is “The Little Ice Age” by Brian Fagan that deals with how the colder climate from 1300 to 1860 impacted global civilizations.
Other books I recommend are “The Great Hurricane: 1938 by Cherie Burns, “The Minnesota Weather Almanac” by Mark Seeley and “The Children’s Blizzard” by David Laskin.
Every generation seems to think that the weather in the past was harsher and more severe than at present. Writings as far back as the 1700s have passages describing the weather being more tolerant than it was for the previous generation. There have certainly been periods when the weather has had a stronger impact on human civilization, but the weather records do not show any major shifts in the weather over the past few generations.
Most of us remember Laura Ingalls Wilder’s book “The Long Winter”. That winter was probably very similar to the one experienced locally in 1996-1997; yet, thousands were not on the brink of starvation with no supplies for weeks on end like during the winter of 1880-1881. Instead, our technology and infrastructure has allowed us to lessen the impacts that weather and our climate has on us.
In other words, it has been technology that has changed far more than the weather has.
If asked if the first half of June was above or below average for temperatures, my guess is that nearly everyone would guess below. If you are one of those in the majority then you would be correct as the first half of June did finished below average.
What would probably surprised many of you is that although the temperature so far this month is running below the long-term average, it has been by only 1.5 degrees, which would be more accurately referenced as “near average”. You may recall that the first half of May was also colder than average, but last month was much more pronounced as that stretch was 8 degrees below average. The first half of this month gave the perception of being much colder than it was probably because of the abundant cloud cover and numerous light precipitation events.
It certainly will not take much of a pattern shift for June to be our 4th straight month with above average temperatures.
Several individuals have inquired in recent weeks asking if the oil in the Gulf of Mexico will impact the weather or hurricane development. More specifically will the oil change the albedo (amount of sunlight reflected) of the water, therefore causing an increase in temperature. This warming of the water would in theory increase the strength of approaching hurricanes and perhaps increase rainfall amounts in the United States.
Contrary to popular perception, the oil does not make the surface of the water darker and therefore allowing the water to absorb more sunlight mainly because the Gulf of Mexico is already very dark and absorbs more than 90% of the sunlight that strikes it. There certainly could be some very small areas where the oil may raise the temperature beyond what would have otherwise occurred, but only in periods of light wind and small wave action. Therefore, as a whole, the Gulf will not have an increase in temperatures because of the oil leak.
It was June, 1752 that one of the most famous and dangerous weather experiments may have been conducted. Most of us have seen the artist rendering of the scene and heard the story of Benjamin Franklin’s famous experiment of flying a kite during a thunderstorm to determine if lightning was related to electricity.
It is not known for sure if Franklin did perform this experiment, but if he did, it is highly unlikely that the picture of Franklin holding a kite with a key at the end of the string is accurate. If the experiment was conducted in that way, he would have undoubtedly been killed by the electrical charge flowing down the string. In his writings, Ben Franklin was aware of the dangers of lightning and if he truly did this experiment, he probably used the kite to collect an electrical charge rather than waiting for lightning to hit his kite.
Others were not so wise and during the 1700s numerous individuals did die experimenting with lightning.
In my previous blog, I mentioned that during the past 20 years, average annual rainfall has increased 3 inches per year. Although as you might imagine, every year the rain patterns have been different, there has been some consistency to when most of this additional moisture has fallen. Two time periods in particular has attributed to this increase in precipitation. One of those periods has been this time of year.
Average June rainfall since 1990 has increased over one inch and May rainfall has increased a bit over one-half inch. Obviously, not every May and June in the past 20 years has been wet, but a high percentage have and this heavy late spring/early summer rain has attributed the highest percent of the excess rainfall during the past two decades.
The other time period of increased moisture has been during the winter. The average annual snowfall since 1990 has been 53 inches in comparison to the long-term average of 40 inches.
Be warned, I am about to throw a lot of numbers at you, but I think it tells an important story. Since 1881, the yearly average rainfall in Fargo Moorhead has been 21.3 inches. Since 1990, the average has been 24 inches. Those three extra inches has added up to five additional feet of rainfall during our current wet cycle.
Is this climate change or just part of our climate? The first 30 years of record keeping from 1881 to 1910 the average rainfall was slightly higher than what has occurred over the past 20 years and there are some indications that the 1870s were also reasonably wet. We also know from early explorers that this area was probably as wet as it is currently in the 1820s to 1840s.
The current long-term average of 21.3 inches is in many ways an average between 50 years of higher precipitation from 1881 to 1910 and then from 1990 to present mixed with 80 years of mostly drier years from 1911 through 1989 when the average rainfall was closer to 19 inches per year.
The difference is subtle, but subtle changes in our weather as we have learned repeatedly in the past 130 years have immense human implications, yet we need to remember one important fact, there is strong evidence to suggest that this area in the past 2000 years have experienced weather changes far more extreme then what our limited written records would suggest.
One of my lectures or talks I give is called "Status Quo as Climate Utopia". The media and sadly some scientists seem to be under the false impressive that weather/climate have been realitively stable for 100s or 1000s of years and every weather element seems to be extreme, odd, weird, unusual or some other similar adjective . There is zero evidence to support this claim when in reality, the evidence says the exact opposite, that weather in the past 130 years with good records has been remarkablly stable with only subtle changes in comparison to the past.
Far more drastic changes are coming, it’s not a matter of if, but when. In other words, our so-called modern society hasn’t seen anything yet.
Climatological spring runs from March 1 through May 31. The first month of spring, March, finished as the 4th warmest on record and was followed by the warmest April on record. Combined, March and April ranked as the 2nd warmest such period since 1881. Even with the first 13 days of May finishing well below average, this past spring finished as the 2nd warmest on record. The average temperature for the past three months was 48.3 degrees, 1 degree shy of the warmest spring on record set back in 1977.
The current 30-year average spring temperature is 42.7 degrees. To put that warmth in perspective, the past two years the average spring temperature was around 39 degrees, so our spring season was approximately 9 degrees warmer than during the past two years. Rainfall was near the average of 5.15 inches with 5.45 inches officially being measured.
Of note, this past spring was the only spring on record with no measurable snow received.