The chart above, which has been provided by the Intergovernmental Panel on Climate Change Third Assessment Report, shows that temperatures in the northern hemisphere have been increasing since the 1900s. Despite the increase over the last 100 plus years, there was a slight drop in temperatures around the 1980s. However, since then the average temperature in the northern hemisphere has been increasing. The National Oceanic and Atmospheric Administration reports that in 2012 alone, Michigan has had 12 record high heat days.

The above chart shows the average yearly temperature in Michigan from 1895 to 2012. While there have been several ups and downs over the last 117 years, the average temperature to date in 2012 has proved to be the highest at 48.49 degrees. This figure, however, only takes the months January through July into consideration. The highest full yearly average in recent history was 46.93 degrees in 1998. The average yearly temperature in 2011 was about 4 degrees lower than the 1998 average.

The above chart shows average temperatures for May, June and July from 1980 to 2012. While the average temperatures over this time span do not show a consistent pattern, there is evidence that in recent years the average temperatures have been increasing. For example, for the month of July there was about a 10 degree average increase from 2009 to 2011; the climate then leveled off from 2011 to 2012. In May, there was an increase from 2008 to 2010 and in June there was an increase from 2009 to 2010.

The above charts show that not only have temperatures in Michigan been above average, but so have the water temperatures of the Great Lakes. Lakes Superior, which is the largest and deepest of the lakes, has experienced the highest above average temperatures of the five lakes. Lake Huron and Lake Erie (the smallest and shallowest) have experienced the least fluctuation from the average temperatures they have experienced in years past (1992-2011). The elevated water temperatures can be attributed to the higher air temperatures that Michigan and the Midwest region have been experiencing this year.

According to the National Oceanic and Atmospheric Administration, July 2012 was the hottest month on record. Like every state in the U.S., Michigan experienced the extreme heat and has since been suffering drought conditions in certain areas. Due to the current climatic changes we have put together a series of posts that explores current and past precipitation and drought data.

This chart, provided by National Oceanic and Atmospheric Administration, displays the precipitation that fell in Michigan during the months of May and June for each year from 1900 to 2012. While precipitation amounts vary over time for the state, this chart shows precipitation amounts from May to June of 2012 are at about 150 mm, or 6 inches. In 2006 and 2007 precipitation amounts were at about 130 mm, or 5 inches. While May-June of 2012 hasn’t experienced the lowest amount of precipitation in the last 10 years, the precipitation numbers are lower than years 2008-2011 during the months of May-June.

In Michigan, July typically has less precipitation than June. This chart shows that over time the recent amount of precipitation the state has received has been in accordance with the long-term average amount of precipitation typically received during these two months. According to NOAA, the long-term trends for precipitation in June and July are about 3.1 and 2.9 inches respectfully.  The 2012 average for June of 3.09 and the 2011 average for July (which is the most recent data) is the lowest it has been since 2009. The precipitation amounts appear to spike and dip in a somewhat cyclical trend so this slight dip is relatively normal.

This drought map, reflecting conditions through July 24th 2012, shows several areas in the State of Michigan that are experiencing moderate drought or abnormally dry conditions. The majority of the Upper Peninsula is considered to be abnormally dry and much of the southern part of the state is considered to be experiencing severe drought; small portions in the southern areas of the state are also in extreme drought.

On July 25, 2012, the United States Department of Agriculture (USDA) deemed 76 counties across six Midwestern states as natural disaster areas due to drought conditions causing large crop losses for farmers.  In addition to counties declared as natural disaster areas on July 25, there are about 1,300 total counties across the Midwest states that have been deemed natural disaster areas. The Michigan counties currently deemed natural disaster areas are Berrien, Branch, Calhoun, Cass, Hillsdale, Jackson, Kalamazoo, Lenawee, Saint Joseph and Van Buren.

This chart shows the number of years with drought conditions in Michigan from 1913 to 2012. In the three most recent 25 year periods examined here, there were about 15 years in each period where Michigan was affected by drought; this is equivalent to about 60 percent of the time. In the time period from 1913 to 1937, when the state of Michigan was most affected by drought, 18 of the 25 years were affected by drought conditions; this is equal to 72 percent of the time.  While Michigan is experiencing extreme drought this year this chart shows droughts in Michigan have been fairly common over time.