# Maximum temperature

Directions for Part A:

Part A includes graphs that will help you understand and interpret changes in precipitation, temperature and other factors and their potential relationship to global warming. Part A also includes questions for you to think about regarding the graphs. You will be able to access the answers to all of the questions posed.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?

The overall trend as a decrease in the average annual maximum temperature, until approximately 1982, when the temperature value increased significantly though the end of the decade. 2. How does the maximum temperature at the beginning compare with the end?

The maximum temperature at the end of the period was nearly as high as it was at the beginning, with the increase occurring over a much shorter time period.3. How does the maximum temperature in the late 1970s compare with the end of the 1980s?

The maximum temperature in the late l970s was at its lowest point, while at the end of the decade had reached some of its highest levels of the 30-year period.4. What could explain this?

The late 1970s were associated with some of the coldest and most severe winter’s in U.S. history. January of 1977 was the coldest January in the history of the U.S., and several studies were done of the likelihood of descending into another “Little Ice Age”. Overall, the increase of the maximum temperatures in the final decade of the data presented may represent the first indications of human-induced “global warming”.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean? Answer:

The overall trend of the average minimum temperature data is a bit different. There is a low value in the early 1980s, but it does not represent the lowest data in the chronologic data set; that occurs at the beginning of the data set in the early 1960s. There are peaks in the early 1970s and at the end of the data set in the late 1980s. The general trend of the 10-year running mean is upward.

1. The average minimum data is acting different from the maximum data.  There are basically 2 peaks, with a small trough in-between.  Is there anything in global warming theory that you have discovered that may explain this earlier increase in the minimum temperature data than what we have found in the maximum data?  How does the minimum temperature at the beginning compare with the end?Answer:

Global warming theory indicates that with increasing global and local temperatures, there should be increased rate of evaporation. This should lead to more moisture being available in the atmosphere. This increased moisture in the atmosphere could lead to more cloud cover/fog/haze, which would tend to hold more heat in the lower atmosphere, leading to higher minimum temperatures.

1. How does the minimum temperature in the late 1970s compare with the end of the 1980s?Answer:

The minimum temperatures, in the 10-year running mean, increases more than 1 degree,  with no instance of a decline over any point of that last decade

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

The averaging of the maximum and minimum data indicates a roughly stable temperature in the first decade, declining average temperatures in the second decade, and rapidly increasing in the 3rd decade.

1. Does the pattern or curve of this line more closely resemble the one for maximum temperatures or minimum ones?  How does the average temperature at the beginning compare with the end?Answer:

The pattern is a mixture of the 2, but seems to more closely represent the maximum data.

1. How does the average temperature in the late 1970s compare with the end of the 1980s?Answer:

The average temperature increased by almost 1 degree over that time period.

1. Although this date terminates more than 15 years ago, what was it indicating in the late 1980s already?Answer:

The data from the 1980s indicated a rapidly increasing average temperature, which seems to support the idea that we were entering a period of rapid global warming.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

Although it varies from year-to-year there is a downward tendency in the size of the daily temperature range, of more than 1 degree Fahrenheit.

1. What would a declining temperature range indicate to us about what is happening to maximum and minimum temperature, since the temperature range is a measure of the difference between the maximum and minimum?Answer:

A declining daily temperature range would indicate that the difference between the daily maximum and minimum temperatures is growing smaller and smaller.

1. Global warming theory indicates that the increased greenhouse gases would cause the Earth’s atmosphere to hold on to night-time warmth more effectively than increases mid-day temperatures.  Does the data tend to agree with that supposition?Answer:

Since minimum temperatures are increasing faster than maximum temperatures, this would appear to be the case. The data does seem to agree with that.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

A rapid increase in the first decade, with a a very slight increase since then.

1. Three of the primary greenhouse gases are water vapor, carbon dioxide, and methane.  Water vapor is a actually the most effective greenhouse gas.  As the temperature rises we would expect more water vapor to be available for precipitation.  Does the data support that kind of supposition.Answer:

Since the levels of precipitation have increased significantly, from 39 inches at the beginning of the period to 42 inches at the end, that would appear to be the case. The complication here is that with increasing temperatures rates of evaporation and transpiration would be increasing too.

17. How does the annual precipitation at the beginning of the data period compare to the end?

Increasing from 39 inches to 42 inches in the 10-year running mean data.  In fact, the last year of  the data set showed precipitation far in excess of any other year.

1. One of the expectations of global warming theory is the expectation of less dependable precipitation and more droughts in the central areas of continental land masses.  Does the data support that supposition if global warming is true?

1. The data does not support the idea that continental land mass areas would receive less precipitation in a globally warmed environment. One of the suppositions is that global warming affects high latitudes more than tropical ones. Therefore, there is less of a temperature difference north to south in the northern hemisphere. This temperature gradient is one of the things that helps drive and create strong storm systems. A weak temperature gradient would mean that continental storm systems (low pressure areas) would be weaker and less able to transport moisture inland from the Gulf of Mexico, resulting in lower precipitation amounts. The data does not support this. Additionally, it should be remembered that it is both precipitation (low amounts) and evaporation (high amounts) that work to provide drought conditions, not just the lack of rainfall.
1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

A general increase, especially late in the period of days of light precipitation.

1. How does the number of light precipitation days at the end of the period compare to the beginning?Answer:

A significant increase, from 168 to 184 in the 10-year running mean, an increase of almost 10%.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

From beginning to end an increase,  However, it peaks in the late 1970s.

1. How does the number of moderate precipitation change compare from the beginning point of the data and the end of the data?Answer:

In the 10-year running mean data, there are 52 days of moderate precipitation at the beginning, it rises to 60 in the late 1970s, and drops to as low as 56 in the late 1980s, an increase over the entire data set, but somewhat depressed during te 1980s.

1. Why might the trend of the data after the late 1970s be significant, and is the upward spike in the last year necessarily significant?Answer:

It may indicate, with increasing temperatures and evaporation, more drought-prone conditions, in the 1980s, due to decreased levels of moderate precipitation.  The last upward spike may not be significant, in that that single year may be anomalous.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

The overall trend, from the beginning point to the end point is down.

1. The heavy precipitation data though shows a different trend from the others.  What is its variability from year-to-year?  When are its peaks and valleys?Answer:

There a concentration of heavy precipitation days in the 1960s.  The 5-year running mean data seems to indicate wide swings in the data from year-to-year.  The peaks and valleys seem to be 1-2 year periods on the 5-year averaged data.

1. Any speculation on the differences we see between the heavy precipitation days data and the others, especially with reference to global warming, or climatic change in general?Answer:

Any differences in the heavy precipitation days would appear to be inconsequential, except with reference to flood or flash-flood events.  The reason is that the number of heavy precipitation events is so small over the course of the year has a small impact, and is demonstrated by the great variability from year-to-year.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

A rapid and steady increase in the number of days of precipitation.

1. How significant is the difference between the number of precipitation days at the beginning of the period and the end?Answer:

221 days at the beginning to 243 days at the end in the 10-year running mean.

1. Because of the number of occurrences, which type of data probably over-biases this curve?Answer:

The number of light precipitation events.

1. Did the precipitation curves give us any indications about the likelihood of the correctness of the global warming theory.  Some speculation, given what we know now would be required.Answer:

The precipitation data alone does not give us definitive information. It does indicate that the amounts of precipitation and days of precipitation indicate increasing levels of moisture which may be the result of increasing temperature, evaporation, and the resulting condensation. The one exception may be the decreasing numbers of days of moderate precipitation in the 1980s.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

A general increase in evapotranspiration, with a peak in the late 1970s.

1. If global warming is correct, would we expect higher levels of precipitation, and with those high levels of temperature, would that lead to higher levels of actual evapotranspiration?Answer:

According to global warming theory, we would expect similar or lower amounts of precipitation, as well as increased levels of evapotranspiration due to the higher temperatures.

1. What happened to actual evapotranspiration during the 1980s and what would that indicate about global warming at this stage?Answer:

Actual evapotranspiration was mostly stable, slightly declining, This, by itself, would have indicated that global warming, as we currently understand the theory was not acting the way we would expect.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

A downward movement from beginning to end.

1. How do deficits at the beginning of the period compare with the end, and what does that indicate about global warming inspired droughts?Answer:

There have been increasing deficits at this location since the late 1970s, which would agree with global-warming induced droughts.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

An increase in the level of surpluses.

1. Are there any significant changes in the annual moisture surpluses over this period?  What does this indicate about climatic change?Answer:

Yes, surpluses peaked at the beginning of the 1970s and at the end of the 1980s, being roughly stable in-between. This would not seem to support the idea of global warming induced droughts.

1. In the figure above what is the overall trend represented by the data, especially the 10-year running mean?Answer:

The overall trend is an increase in runoff, which should translate into increase surface and stream flow.

1. Compare the amount of runoff (available surface water) from the beginning to the end of the period.Answer:

An increase from 13.2 to 15.5 inches from the beginning to the end of the period.  An initial peak in the early 1970s reached 15.1 inches.

1. Is there anything distinctive about the pattern of runoff in the 5-year running mean and the peaks that are being generated?  It would seem to mean that, at least during this period that precipitation was staying ahead of evapotranspiration.  If that is the case, what might it mean for global warming and climate change?Answer:

The 5-year running mean data seemed to run in 2-3 year cycles of maximums and minimums, but the peaks of the cycles grew to higher and higher levels.  This data, by itself, would not appear to agree with the consequences of global warming, as we have understood them to this point.

Your completed Project 2 Part B, should total approximately 8 pages, double-spaced, roughly 2000 words.

• Do we see an overall warming of the environment?
• Some theorists envisioned that we would see a more pronounced warming of minimum temperatures than maximum temperatures.  This might result in a reduced range of temperatures.  What trends does the data show?
• Many theories that look at global warming envisage more drought and less surplus water conditions for inland or continental locations.  Therefore, we might see some trends in precipitation amounts and the frequency of certain amounts of precipitation.  What do the trends show?
• In reference to actual evapotranspiration, surplus/deficit conditions and runoff/streamflow, what might we expect with a warming climate?
• Are there clear-cut answers in the trends that we see?
• What does that tell us about researching environmental issues like global warming?
• Are there other types of data or information that we need to look at to make a worthwhile analysis?  If so, what would they be?
• What are the implications of the results of this study?
• Can you link any of the climate trends to human agency?
• If the trends continue in their current direction, what are the potential implications for people living in the Wabash Watershed?

In short, we are looking at a specific geographic area, the Wabash Watershed.  We are looking at a specific time period, 1961-1990, utilizing raw, 5-year average, and 10-year average data, with respect to temperature, precipitation, evapotranspiration, moisture surplus, moisture deficit, and surface runoff.  What does this data tell about this region over this time period, and what does it indicate about the future?  Does this tell us anything, positively or negatively about global warming theory?

These are just some of the questions you should ask yourself as you analyze and report on this data and tell us what it all means. Good Luck!

Be sure to submit your project in one Word file and document your sources using APA format.