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Map Selection Regional Temperature Records from the Last Century
 A Latitudinal Gradient
Temperature records from the northern Great Plains and Rocky Mountains during the last century reveal both regional variability and long term trends. The map below shows the geographical distribution of annual temperatures in the 5-state UMAC region averaged over the 120 year period from 1880 to 2000. A latitudinal gradient with colder temperatures (yellow) to the north is apparent toward the eastern part of the region, which is dominated by continental weather patterns. The other cold region on the map reflects high elevations in the Rockies. Away from the continental interior, toward the western part of the region, warmer temperatures (red) demonstrate the moderating effect that marine systems have on continental climate. The map patterns illustrate mean climatological conditions. However, this does not give any insight into how conditions may be changing over time.100 Year Data
Maps of temperature for the northern Great Plains and northern Rocky Mountains (MN, ND, SD, WY, MT, & ID) have been created using 100 year monthly averaged values acquired from the National Climate Data Center (www.ncdc.noaa.gov). The dataset is known as the United States Historical Climatology Network (USHCN). The USHCN is comprised of 1221 high-quality stations from the United States Cooperative Observing Network within the 48 contiguous states. The period of data recorded varies for each station but generally includes the years 1900-2000.Linear Trends
Climate trends for each of the UMAC states are different, which emphasizes the importance of a regional assessment process. The temperature time series shown for each state represents a 5-year running average with a calculated linear trend. Degrees of warming are given to the right of the state name. Click on the time series to open up a detailed graph for the individual state.Interestingly, not all states show the same warming trend over the last century. Idaho, Wyoming, and Montana trends indicate the average temperature has increased by around .5 to 1 degree in these states. Minnesota and North Dakota both show warming trends between 1.5 and 3 degrees, which is higher than the global average, and South Dakota beats them all with a change of 2.28 degrees. Regional Temperature Patterns
 Temperature Differences
Not all regions are affected in the same way by global scale change. For example, while globally averaged temperatures for 1997 exceeded all previously recorded measurements, many regions actually were cooler than average during that year.Am I Getting Warm?
The map to the left shows the difference between 1997 annual temperatures and climatological temperatures averaged over the previous 100 years. This map of temperature anomalies illustrates red areas as warmer than normal temperatures and blue areas as cooler. While broad areas in all UMAC states experienced warmer than average conditions in 2000, a small portion of the states Montana and Idaho were cooler than average.Clearly, when exploring the consequences of climate change, it is important to understand regional trends apart from the global average. The link to the temperature anomaly movie shows how the climate has been getting warmer for our region during the last century. Global Climate Change
 Global Warming?
For at least a decade now, global warming has been an issue of public concern and debate. Is the temperature rising? Measurements collected from around the world indicate the answer is yes, global climate is warming. In fact, it is apparent that the 1990's were the warmest decade of the last century, with 1990, 1991, 1995, 1997, and 1998 all being record-breaking years. The year 2001 is second to the warmest year 1998 in the last decade. These warm years support the answer that climate is warming.The graph shows a record of global temperature change since 1880. This is a way to show how each year compares to the long term average. Positive values are warmer than normal and negative values are colder. A Warming Trend
Since the industrial age began annual global temperatures have steadily increased and are now consistently warmer than average, even during relatively cool years. In the last century the average temperature of the planet has increased by over 1 F. If this warming trend continues, how will this affect our lives, the environment we live in, and the resources we depend on? What does "global climate change" mean for the region in which we live?
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