Images/Tutorial

Working with and Analyze Archived Local Weather

A major assignment in this course introduces us to weather sites which contain tons of data about every kind of weather phenomena. I will be focusing on the Midwest for my data analysis.

Overall, there has been an increase in temperature from 1895 to 2014 for the month of March. The trend of the increase is very miniscule but there is nonetheless a positive trend. It appears that every two or three years there is a large spike in temps and then it drops down the next year by roughly the same amount each time. The spikes in temperature have, in the past 30 years, been getting higher and the colder years aren’t as cold as the previous years. So even though the overall trend is barely positive in recent times it is much more positive. March, this year, was just colder than last year; not even a degree separates the two years. Compared to the average temperature of 41.5 degrees Fahrenheit this year comes in just under that at 41 degrees. This small deviance from the average may not seem like a big issue but if the average were to be taken for the past 30 years you could see that the average has risen in those years specifically.

Figure 1. Line Graph displaying the average temperature for March in the Contiguous U.S. from 1895-2014. A trendline is included to show the trend in temperatures over the course of recorded weather data.

For Wisconsin specifically, the trendline is relatively the same as the national average. Even though this March was colder than last year the spikes in temperature have been more constant and at a more consistent temperature range with 2012 being the exception since it is the warmest March on record. Given the trend of spikes in March for temperature I would say 2015 will have a very warm March and a fast snow melt because of it.

Figure 2. Line Graph displaying the average temperature for March in Wisconsin from 1895-2014. A trendline is included to show the trend in temperatures over the course of recorded weather data.

 Precipitation levels for the contiguous have the most minimal increase since 1895 for the month of March. 2014 had more precipitation than 2013 but the amount is still below the trendline. With the overall trend in spikes dropping I anticipate next year being relatively the same if not lower than this year. Overall there seems to be no real pattern in the precipitation but since the 70s the average has fallen by about half an inch. If this recent trend continues it will, of course, bring down the national average providing clear evidence that as temperatures are rising the amount of precipitation is dropping.   

Figure 3. Line graph displaying precipitation totals for March in the Contiguous U.S. The graph includes a line showing the overall average of precipitation. Since the 1970s precipitation values have been dropping in the month of March for the U.S.

Precipitation level for Wisconsin contradict what the rest of the nation has experienced. The trendline for Wisconsin is barely positive showing precipitation increasing by a quarter of an inch. With this small increase in precipitation for Wisconsin it would be interesting to see if the rest of the Great Lakes region has experienced a similar increase for the month of March. Last year the precipitation amount was above the trendline but this year it is way below it. There should be an increase in precipitation next year for Wisconsin but I don’t believe it will all be snow considering the rising temperatures. 



Figure 4. Line graph displaying precipitation totals for March in Wisconsin. The graph includes a line showing the overall average of precipitation.

 States experiencing above average temperatures lie along the West Coast of the United States and into the Southwest including New Mexico, Colorado, Utah, and Arizona. The East coast as a whole experienced a very cold March. The New England and Great Lakes regions experienced temperatures much below the average for the regions. Because the Eastern half of the country experienced colder temps I have to assume that the temperature experienced on the West Coast is considerable enough to help the trendline continue to increase for the national temperature average.

Figure 5. Regional Temperature Ranks for the Contiguous U.S. You can easily see that the Western half of the U.S. has experienced a much warmer year compared to the East which has felt a colder year than average..

Regional precipitation values have been very average in 2014 compared to the average for the month of March. Areas experiencing an increase are states in the northwestern region of the Contiguous U.S. and states experiencing a decrease in March are all of the states in the Great Lakes region and the states to their south and those around Texas.

Figure 6. Regional Precipitation ranks for the Contiguous U.S. for the Month of March 2014 compared to the average. There is area which is below the average for their region in the center of the U.S. This could be due to not having a large body of water for moisture to be brought in by.  

The ten coldest years (coldest to warmest): 1965, 1912, 1960, 1969, 1906, 1915, 1924, 1932, 1899, 1958.

Top ten warmest years (warmest to coldest): 2012, 1910, 2007, 2004, 1946, 1921, 1986, 2000, 1918, 1907.

Since 1985 four of the top 10 warmest years have been since 2000. The time in-between these recently warm years is far closer than the time between any of the other years. This is telling that the temperature is increasing at an accelerating pace. To make a more informed decision as to whether or not one believes in global warming they could look at temperature trends for the entire year instead of focusing on one month. A yearly trend would be much more beneficial since it doesn’t narrow its focus so much. Since 1985, though, the temperature has been increasing at a rate which is much faster than it is for the month of March.

 All data above came from NOAA Climate at a Glance