MET 101 Ch 15 Current Weather Studies

Click on Local. From the menu tabs bar (above the Observed Weather Reports heading), click on "Climate Locations". There are ________ climate reporting sites in the Hawaiian Islands.

5

At the bottom of the page, click Teleconnection Forecasts. Then on the following page, under Daily Forecasts of Teleconnection Indices for Last 120 Days, the North Atlantic Oscillation(NAO) [(35-45N, 70W-10W) - (55-70N, 70W-10W)] is listed. Note the "NAO Composite Phase Maps" to the right. The bottom Northern Hemisphere map is of surface temperature anomalies (SFCT), differences from average seasonal temperatures. The shading shows that, in general, there ________ variations in the hemispheric temperature pattern around the North Atlantic Ocean region. Blue-to-red shading contrasts would likely be related to the North Atlantic Oscillation. Thus, specific geographically related climatic non- uniformities have been identified and are used to predict local weather conditions for periods into the future.

Are

Average temperatures tend to be lowest in the middle and higher latitudes of the Northern Hemisphere during the months ________. This is primarily due to the shorter days and lower position of the sun in the daytime sky, which decrease the amount of solar energy received at these latitudes.

December through February

In California (and much of the West Coast of the United States) the driest season occurs in ________. The lack of rainfall in this season is due to California's location on the east side of a center of semi-permanent subtropical high pressure that exists over the Pacific Ocean centered near Hawaii mainly in the summer, and the presence of a cold ocean current off the coast (the California Current).

June, July, August

Under the heading Climate Prediction Web sites, click on "Climate Prediction Center (CPC)". The blue rectangle bars containing links show the outlooks from "6 - 10 Day" out to "Three Month" are given for ________. Running your cursor over the category types displays the current map of the anomalies.

Percipitation

Back on the menu tabs bar, click on "Climate Prediction" to display a page providing information on climate prediction and variability. The left table column lists long range forecast periods that have linked climate products. These products are for periods of ________. You might note that for periods up to two weeks, the NWS terms the prognostications "forecasts" while longer periods are termed "outlooks" to reflect the degree of certainty in the predictions.

all of these periods

In the Raw data maps section on Rainfall, click on the map of "Annual average rainfall total" (in millimeters). The annual average masks the seasonal variability and reveals how wet or dry a particular region is. Some of the driest places in the world (<75 mm, appearing white and light gray on the map) occur in the interior of large continents which get little or no rainfall year round, due to distance from water sources, the effect of mountain ranges, and perhaps other factors. The center of the Sahara Desert in Africa and the Gobi Desert in the interior of Asia likely ________ fall into this category.

do

Climates classified as A: Tropical occur as expected near the ________.

equator

This pattern of extreme seasonal dryness ________ similarly found in the southeastern U.S., which is located on the western side of a high pressure zone (centered near Bermuda) and near a warm ocean current (the Gulf Stream).

is not

The wettest months in India occur in ________.

late spring through early fall

D and E represent climates of the ________.

midlatitudes and polar regions

In Raw data maps, go to the Temperature section. Click on "Animation of monthly temperature" for a map which automatically cycles through the months of the year depicting how temperature changes through the months across the continents. Or you may click on Average monthly temperature: "January". Then select each month, in sequence. Based on the maps, average monthly temperatures vary more during the year near the ________.

poles

The B: Dry climates generally occur in ________ parts of the world that receive relatively low annual amounts of precipitation. (Note, parts of the color coding for classifications A, C, and D overlap into regions which under most classifications would be considered B: Dry climates because they are mapped based on the temperature criterion alone.)

the same

Other places are dry primarily due to the effect of mountain ranges which tends to "wring out" moisture from air. The location of the desert in these situations depends on the orientation of the mountain range and the direction of the prevailing wind. One of the driest deserts in the world is the Atacama, midway up the west coast of South America. Here, persistent winds from the east create a narrow, dry rain shadow on the western slopes of the Andes Mountains down to the Pacific Ocean. The dryness is enhanced by a cold ocean current which discourages the uplift of air. Further south, at a higher latitude, in a zone where the prevailing winds come from the west, the coastal zone is moist and the rain shadow desert is found to the east of the Andes Mountains. In North America, the driest areas occur just east of the north-south oriented western mountains. This would suggest that at these northern latitudes the prevailing wind blows from the ________.

west