Lab 15 a - Meteorology

Climate classification systems allow climate differences and similarities to be expressed in a "shorthand" form. The broad-scale climate boundaries in the Köppen Climate Classification System (see Climate Classification at the end of this investigation) are based on patterns in annual and monthly mean temperature and precipitation, which closely correspond to the limits of vegetative communities. The major classifications of Tropical Humid (A), Subtropical (C), Snow Forest (D), and Polar (E) are based on temperature; the group Dry (B) is based on precipitation; and the group Highland (H) applies to mountainous regions. Temperatures for both Fairbanks and Detroit place them in the ________ classification.

snow forest (D)

Columbia, SC at about the same latitude as Yuma, but in the southeastern United States, is humid because it is located ________ of such a high pressure system in the Atlantic.

west

Your completed climograph for Detroit, MI (Figure 1) shows that the mean monthly temperature rises from below freezing during most of meteorological winter (Dec., Jan., Feb.) to means over 70°F during July and August and then falls as winter approaches. The observed temperatures from which the means are computed result mainly from the seasonal swing of solar heating, which in turn is largely determined by latitude. As a general rule, the higher the latitude the lower the winter season temperatures. The lowest mean monthly temperature in Detroit occurs in ________.

January

Arid and Semiarid climates can be caused by several climate controls. Locations on the eastern side of planetary-scale, persistent high pressure systems, such as those occurring around 30 degrees N in the Atlantic and Pacific, experience subsiding air, which inhibits cloud formation and precipitation. The west side of such systems, by contrast, tends to be humid. The cause of dryness in Yuma AZ, for example, is due mainly to its position ________ of a subtropical high pressure system which persists off the southwest U.S. coast in the Pacific.

east

These temperatures suggest that Fairbanks is a ________ latitude location.

high

It is likely that Kahului's relatively low annual temperature range ________ also moderated by the surrounding Pacific Ocean.

is

This minimum monthly temperature ________ within a month of the time of minimum solar heating at the midlatitude, Northern Hemisphere location.

is

Compare the annual temperature range for Detroit, in the north-central part of the country, (Figure 1) and Eureka, CA, on the Pacific coast, (Figure 5). Eureka's annual temperature range is ________ that of Detroit.

less than

From the shape of the curve and range of temperature, it is evident that Kahului experiences relatively ________ variation in solar heating through the course of a year.

little

These temperatures suggest that Kahului is a ________ latitude location.

low

The month of occurrence of the highest mean temperature suggests that Kahului is located in the ________ Hemisphere.

northern

Detroit and Eureka are at similar latitudes and both are located near a large body of water. The climate control causing the difference in annual temperature range is the influence of the prevailing westerly wind at both locations. For Eureka, the temperature range is influenced mainly by the ________ which is upwind and in Detroit by winds blowing from the continent with the nearby body of water being downwind.

ocean

Dry or wet conditions can also be caused by a location being upwind or downwind of a mountain range. Areas to the lee of high mountains tend to be dry because of the "wringing out" of moisture on the wet, windward slopes (due to orographic lifting, cooling and condensation) and the compressional warming of air which occurs as the air descends on the leeward slopes. The atmospheric stability caused by cold ocean currents offshore can also prevent precipitation by stabilizing the air and inhibiting convection. Instability, however, can occur if ocean currents are warm. The dryness of Yuma, which is downwind of the Coastal Ranges and the cold California Current, is ________ drier because of the influence of mountains and ocean currents.

probably

the climate control primarily influencing local climates is the prevailing wind circulation from ___________.

proximity to large bodies of water

The second letter of the Detroit (Figure 1) and Fairbanks (Figure 6) classifications corresponds to seasonal precipitation regimes with an "f" signifying year-round precipitation. According to their climographs and climate classifications, Detroit and Fairbanks have ________ month-to-month uniformity in their precipitation regimes.

similar

The lowest monthly mean temperature for Fairbanks is about ________°F.

-10

Where solar heating varies significantly from the winter to summer solstices, the range of temperatures, indicated by the amplitude of the temperature curve on a climograph, is relatively great. Where the amplitude is relatively small, the seasonal temperature contrast is also small. Examine the temperature curve on the climograph for Kahului, HI (Figure 2). The range of mean monthly temperatures for Kahului is about ________ Fahrenheit degrees.

10

Examine the climograph for Fairbanks, AK (Figure 6). The highest mean monthly temperature is about ________°F.

62

The average monthly temperatures in Fairbanks cover a range of about ________ Fahrenheit degrees.

70

The lowest mean monthly temperature is about ________°F in both January and February.

72

The highest mean monthly temperature in Kahului occurs in August. This temperature is about ________°F.

80

This range of temperatures suggests that Fairbanks has a ________ climate.

continental

the region of Tibet in south central Asia is the greenish-brown of a polar climate even though it is surrounded by dry temperate climates. this classification is most likely the result of Tibet's

elevation