Chapter 14
Applied Climatology, Climate Impacts, and Climatic Data
2. The text compares applied climatologists to detectives. In what way do you think this comparison is
valid?
Answer: In many ways the work of an applied climatologist is similar to a detective. Applied
climatologists must act as a detective by trying to determine the most likely conditions at the time of
interest. Applied climatologists, like detectives, must be adapt by making educated guesses about
atmospheric conditions when reliable data are not available. This may involve estimating conditions
through the interpolation of data nearby or making an educated guess. Applied climatologists are often
called to give their expert testimony in court just as a detective would do.
4. How does the total of heat-related deaths compare to that of cold-related deaths in the United States?
Answer: Temperature extremes cause numerous deaths each year in the United States. Although heat
wave events may result in a massive number of fatalities over a large region, cold waves are more likely
to cause a larger number of isolated deaths. In total, deaths from cold weather seem to be more numerous
than hot weather, even if increased severity of diseases from cold weather events are not included.
6. What advantages do HPD provide that are not provided by LCD?
Answer: Hourly precipitation data (HPD) and local climatological data (LCD) are both published
monthly by state. HPD data provides the maximum intensity of precipitation to fall within specific time
periods. HPD also allows the researcher to see the temporal distribution of the rainfall. Determining the
temporal distribution of the daily rainfall could be useful for various climatological applications,
especially hydrologic and agricultural studies.
8. Why is the time of observation a critical variable in applied climatological analysis?
Answer: Time of observation of atmospheric variables is an important consideration when conducting
applied climatological analysis using data from daily-reporting stations. The bias toward lower
temperatures has increased over time as a result of many stations changing from reporting in the afternoon
to the early morning. The lengths of heat waves are likely to be magnified by afternoon-reporting stations
and the time periods of cold waves are often extended by morning-reporting stations. The observed
temperature trend despite the fact that temperatures have risen substantially over the last 30 years
provides further evidence that the observed warming is significant. Time of observation is also critical
when analyzing daily precipitation data, especially in regions that are dominated by convective
precipitation.
10. What is the difference between a crop heat unit and a growing degree-day?
Answer: A growing degree-day is a variable that is accumulated for each degree that the daily mean
temperature exceeds some base value, which varies according to the type of crop. The base temperature is
the minimum daily temperature required for a crop to grow. A crop heat unit calculates two base
temperatures, one for the daily minimum and daily maximum temperature. Similar to growing degreedays, if the daily minimum and/or maximum temperature is below the base temperature, zero crop heat
units would be accumulated. Crop heat units are more commonly used in Canada.
12. A traffic accident occurred on the corner of Final and Exam Streets on a particular day and time. What
sources would you consult to identify the weather conditions at that place and time?
Answer: To examine the atmospheric conditions associated with the traffic accident you could use
several data sources. Climatological Data could be utilized to note if any temperature extremes occurred
on the day of the accident. Local Climatological Data may possibly indicate the conditions at a finer
temporal scale if data are available from a nearby site. Hourly Precipitation Data would be the best source
of data to analyze hourly precipitation characteristics surrounding the accident, such as the maximum
intensity of precipitation for a specific time period. Storm Data may provide further evidence of severe or
unusual weather that may have occurred on the day of the accident. NOAA’s Daily Synoptic Series can be
used to determine if any frontal systems or upper-level disturbances affected the region. Finally, hourly
satellite and radar products may provide additional clues to the characteristics of the atmosphere during
the time when the accident occurred.