Exercise 1
Weather Map Symbols
Here is a current surface map of pressure centers and fronts. As you can see the fronts are only a general boundary, the air mass is behind the front. Cold fronts are blue with triangles, and warm fronts are red with half circles. the Triangle and half circle side is where the front is pushing towards.
Here is a map of the air mass patterns for North America. Warm mois air comes in from the gulf and Pacific. Cool moist air comes in from higher up in the Pacific and Atlantic. On the land we get hot dry air from Mexico, cold dry air from Canada in the winter, and warm dry air from Canada in the summer.
Low pressure will spin counter clockwise north of the equator. High pressure spins clockwise north of the equator. The opposite happens when these pressure systems form south of the equator. Low pressure centers will push air up and in, and high pressure will push air down and out.
From this map I can see that most of the sky is clear in
this region. You can also tell that winds are moving faster near the rockies.
Other than that California is getting wind from the north and it’s curving to
the west as we move inland. I can’t fix a pressure system, but it looks like we
have high pressure in Utah and the wind direction would facilitate that.
Since the barometric pressure is rising we won’t be seeing any
precipitation for a while, and we can expect this cold dry air to continue as
well.
Exercise 6
Contiguous U.S. Temperature Multigraph
Looking at this graph of temperatures in March every year we can see hat there is a pattern of warmups and cooldowns each year. It might not be every year, but on average it seems to warmup and cooldown consistently over time. It also appears to be getting warmer as the years progress. The average temperature is 41.5 degrees, and since about 1980 we've been hitting above that line except for 5 or 6 years. This year it was just a tad bit colder then last year from 40.89 F to 0.51 F.
The Wisconsin temperature multigraph follows the same pattern as the above multigraph except temperatures are much colder. Recent temperature readings seem to be slightly warmer and not as far away from the average temperature line. One interesting fact however is that this year was one of the coldest on record, and the year before was also very cold, but the year before that it was the warmest on record.
Wisconsin Precipitation Multigraph
Precipitation has an overall rend much like temperature. We have very wet years that are above average, and very dry years below average. These two types of years can be seen on the graph over a period of 1-5 years. This year we had very low amounts of precipitation compared to other past years. On average we're seeing 1.8 inches and patterns haven't really changed much over the course of the century.
It would appear from looking at this map that the southwestern United States experienced the most above average temperatures for the month of March.
It would appear from looking at this graph that the 10 warmest years were 2012, 1987, 1998, 2000, 1990, 2006, 1931, 1992, 1921, and 1983. The top 10 coldest years were 1912, 1899, 1936, 1904, 1979, 2014, 1917, 1895, 1978, and 1965.
It's hard to say what effect these values have on climate change. In 2012 we had the warmest year on record, and now in 2014 we had the 6th coldest year on record. Climate patterns over a long term are the key thing to watch because of the average. If average is increasing or decreasing then we know global climate is changing. It's also important to monitor anomallies like ncdc does. Volcanic activity has major impact on climate as well as other things like pollution to name a few. In the case of predicting climate change the more information you have the better you can predict it.
Madison Weather
Here we can see that the highest temperaures in Madison are recorded in the summer months of July. this is because Madison is receiving the most radiant energy from the sun in this month. In contrast January receives the least radiant energy from the sun therefore it is the lowest temperature.
Madison has it's highest precipitation in August, and lowest precipitation in January. Precipitation is simply anything that condensates in the atmosphere and falls due to gravity. This can be snow, hail, sleet, rain, or whatever combination you can come up with. Precipitation fluctuates year to year, but always follows a flooding pattern.
The warmest month in Milwaukee is July, and the coldest month is January. This once again has to do with the amount of radiant energy the sun gives off.
Milwaukee's highest precipitation month was April, and lowest month was February. Precipitation is simply anything that condensates in the atmosphere and falls due to gravity. This can be snow, hail, sleet, rain, or whatever combination you can come up with. Precipitation fluctuates year to year, but always follows a flooding pattern.
Minneapolis, Eau Claire, and La Crosse Climate Report
Minneapolis:
Year to date precipitation - 5.69 in.
Since July 1 snowfall - 69.8 in.
Eau Claire:
Year to date precipitation - 6.60 in.
Since July 1 snowfall - 74.8 in.
La-Crosse:
Year to date precipitation - 7.69 in.
Since July 1 snowfall 48.9 in.
It looks like Eau-Claire got the most snowfall this winter while La-Crosse got the least snowfall. However La-Crosse got the most precipitation since January 1 while Minneapolis got the least since that time. La-Crosse probably got the least snowfall because it's more southerly than the other two. The direction of most of our alberta clippers this year would have missed La-Crosse more of the time. Colorado lows were more in the path of La-Cosse, but we didn't get as many of them in the Midwest.
The records date back to 1961 which could be a problem since it only goes to 1990 which is less than 30 years of data. It's hard to predict trends in that period of time as well as true record lows and highs.
The Eau-Claire climograph was made through archived data. It shows a high temperature reached in July and most precipitation in August. It also shows low precipitation in February and low temperature in January.
The Minneapolis climograph was made through archived data. It shows a high temperature reached in June and most precipitation in June. It also shows low precipitation in January and low temperature in January.
The La-Crosse climograph was made through archived data. It shows a high temperature reached in July and most precipitation in August. It also shows low precipitation in January and low temperature in January.
The Madison climograph was made through archived data. It shows a high temperature reached in July and most precipitation in August. It also shows low precipitation in January and low temperature in January.
The Milwaukee climograph was made through archived data. It shows a high temperature reached in July and most precipitation in April. It also shows low precipitation in February and low temperature in January.
The Superior climograph was made through archived data. It shows a high temperature reached in July and most precipitation in August. It also shows low precipitation in February and low temperature in January.
The Wausau climograph was made through archived data. It shows a high temperature reached in July and most precipitation in August. It also shows low precipitation in January and low temperature in January.
Why is it useful to compare your data to more than one of these locations?
Some of the data locations only went back to 1961 while others dated back to the 1800s. Data locations could also be at different altitudes which means different weather patterns. Some locations may be missing data, or have obscure data collections. I collected data for these graphs from local airports if the city had them because they seemed like the most reliable source of information. However the more data that has been collected is always the best choice for accuracy.
What variables may influence differences between those locations and our location?
Longitudinal differences between the other locations is my first thought. Some areas are more south of us and some areas are more north of us. This mostly relates to differences in temperature. Another factor could be their proximity to lakes because. There is such a thing as "lake effect" precipitation. This type of precipitation occurs in late autumn and early winter months. It's the result of rapid warming and moistening of continental polar air masses that move southward from central Canada. The moistening occurs when water from the Great Lakes is evaporated into the cP air mass, causing an increase in dew point temperature. The warming of the air occurs as a result of the temperature contrast between the cP air mass and the lake surface. This is much like how "lake-effect" snow works. Finally storm patterns vary year to year so one year Madison could have high precipitation, and another year have very little.
How might these data vary from your data regarding your collection techniques?
Data varies depending on the source you used on the worldclimate site. Depending on the source you used data will be different.
The obvious trend over the late winter months is upward. We had a pretty rough winter this year as you can see by the lows over the months of January and February. Even the mean temperatures were very low in these two months. In January it averaged below zero!
Because we didn't have very much precipitation in January we must have had very little cloud cover which lead to more heat being released from the surface and colder temperatures. We've been getting a lot of precipitation so far in April, and this is because of temperatures warming, and air mixing as the polar jet moves north.
I had a hard time making this pie chart with wind directions so I will explain it here. The gray area represents a generally west wind for the months of February and April. the blue area represents a west northwest wind for the month of January. Finally the orange area represents a southeast wind for the month of March.
Dominant wind direction has been coming from the west. This could be because of the direction most storms took this year which was northwest of us. These low pressure storms circulate counterclockwise which would mean they would hit us from the west. Because winds were generally out of the west we wouldn't see much for precipitation. I'm saying this from the folk lore of winds out of the east and that relation to high precipitation.
The only anomally I see in this data is the low precipitation through the months of January and February. I don't know if they weren't considering snowfall as precipitation, but it just seems really odd. Because of the generally cold weather we had this winter, and the direction of storm patterns we didn't get as much precipitation as we could have. Areas like Superior and Duluth saw much more snowfall then we did because of this. I don't exactly know how the bitter cold relates with precipitation, but we aren't near any huge lakes like Milwaukee is. Because of this we don't get that warming of air mass over the lakes that allows condensation to occur which effects precipitation. We generally rely on those heavy Colorado Low systems moving in from the south to generate our big blizzards. Since winds were mostly west, these types of systems couldn't carve a path high enough to reach us. Also Alberta Clippers generally missed or only nicked Eau-Claire and went further north this year.
Data and graphs retrieved from the 2014 Eau-Claire metastation archive at http://metstation.uwec.edu/NOAAYR.txt
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