Sam Wolfand 1. a. Washington’s Average Annual Temperature:
b. Washington’s annual temperature range: c. Washington’s annual Precipitation: ( ) )
2. Does Washington have a marked wet season? Yes, the summer months are all above the 50 cm line in terms of precipitation which would indicate the Washington DC has a wet season that occurs during the summer 3. What other information can be gleaned from the climograph: The climograph also shows that temperature in Washington DC is highest when precipitation is highest. Furthermore, it’s shown that that Washington DC has average average temperatures in winter that are typically just above freezing. Also, the temperature from summer to fall declines slowly, while the temperature from fall to winter it declines more rapidly. Furthermore the lowest amounts of precipitation in Washington occur during the times when the temperature is the lowest. Taking all this into account, the mild winters it can be inferred that Washington DC exhibits characteristics of a Mid Latitude location 4. Other Sample Climographs a. The temperature of the climate is relatively uniform throughout the year with a very short dry season. At least 10cm of rain occurs during at least 7 months of the year, and the dry season is from December to April. Due to the uniform temperatures this climate station is most likely tropical monsoon b. There is very little to no rain during all months of the year. The highest amount of precipitation which is maybe 3 or 4 cm occurs during the summer months. There is little to no precipitation during the other months, However there is a large disparity between the lowest temperature and highest temperature. Annual precipitation being
so low and lowest temperature also being so low, the climate is mostly likely a polar ice cap region. c. The average lowest temperature is above freezing (0°c) and the average warmest temperature is lower than 30°c the rainfall varies a lot throughout the year, with peaks in June and September and October. The climograph is representative of a humid subtropical climate like that of Japan. This climate is characterized by lots of rain and mild temperatures in the winter.
5. Why does the annual temperature range increase as latitude increases? The angle of incidence of the sun's rays at the earth's surface increases from the tropics towards the poles as the earth is a sphere and the apparent movement of the sun in the northsouth direction is limited between 23.5 degree latitude N and 23.5 degree latitude S. Therefore the amount of heat received in a given area diminishes from the equator towards the pole. Temperature is therefore normally highest in the tropics (lower latitude) and lowest in the Polar Regions (higher latitudes). Furthermore, due to the tilted axis of the earth, both the North Pole and the South Pole are pointed towards the sun alternatively creating a wide range of temperature between summer and winter depending upon the latitude. Hence the annual temperature varies depending upon the latitudes. 6. While not always true, the three climograph show decreasing precipitation with latitude. Why is there potential for greater precipitation at lower latitudes The equator is the warmest place on earth. Warm air is less dense and rises. When it does that, it cools down by adiabatic effect with altitude and moisture condenses, forming clouds then precipitations.
The poles are the coldest places on earth. Here, the cold air sinks, warms up by the same adiabatic effect and clouds evaporate, giving place to a clear sky and little or no wind. Those are places of high pressures. If it wasn't for the earth's rotation and the resulting Coriolis force, the air that rises at the equator would probably travel to the poles, sink, and come back to the equator at the surface. But the Coriolis force diverts to the right hand any fluid displacement in the northern hemisphere. The air rising at the equator then spins clockwise and sinks at roughly latitude 30 N, and 30 S. This is where you find most of the deserts on earth.
Between those two belts of high pressures and the poles, a front exists at roughly latitudes 60 N and 60 S where the mild temperate air meets the cold and dry polar one. The warmer air rises over the colder one and that sinks the pressure, creating convections where the air rises, cools down and causes clouds and precipitation. That forms the major cells of air displacement on earth, called, from the equator to the poles; the Hadley cell, the Ferrel cell and the Polar cell.
8. Name two other places that that would have different temperature patterns because of contrasting proximity to the ocean Monterey, California 36.6003° N, 121.8936° W and Tulsa, Oklahoma 36.1539° N, 95.9925° W. While both have latitude near 36°N their climates are very different due to the fact that Monterey is incredibly close to the ocean and Tulsa is much more inland 9. Why does Norfolk have a more continental temperature pattern than San Francisco? Because Norfolk is not on the windward side of North America, the typical marine climate pattern is not as prevalent even given the proximity of Norfolk to the water. In this case, due to not being on the windward side of the continent, Norfolk more closely resembles St Louis’s weather pattern 10. Name another coastal location where you would expect a continental temperature pattern Ocean City Maryland is on the coast of the Atlantic; however it is on the non-windward side of North America, and as such I would expect a continental weather pattern. 11. Account for the difference in the annual temperature ranger between Seattle and Spokane. The Cascade Range forces air to rise. As it rises, it cools and the water molecules within condense--a process known as adiabatic cooling. The condensing water vapor forms clouds and water droplets, resulting in precipitation. The side of a mountain range that receives wind and air masses, called the windward side, experiences large amounts of precipitation. Hence, Seattle, Washington, experiences high levels of precipitation on the windward side of the Cascade Range. In Spokane there is less precipitation and higher temperatures because it is on the leeward side of the Cascade Range. The air masses moving over the mountains have dropped moisture on the windward side of the range. Leeward sides of mountain ranges are said to be in a "rain shadow."
12. Name two other cities that you suspect would have contrasting temperature and precipitation patterns because they are separated by a mountain range Gunnison, Colorado, located west of Colorado and on the windward side of the Colorado Rockies, and Boulder, Colorado, located on the eastern leeward side of the Rockies and Considered in the Great Plains region would most likely have the same disparities in temperature and precipitation that Seattle and Spokane do. 13. Why does Los Angeles have lower summer temperatures than Phoenix, which is at approximately the same latitude? The California Current, is a cold water current off the southern half of the west coast of the US, as well as Baja California in Mexico. It's part of the North Pacific Gyre. This keeps the climate of San Francisco, Los Angeles and San Diego cooler than it would normally be for those latitudes. However in Arizona El Niño-Southern Oscillation (ENSO), this weather pattern--caused by superheated equatorial waters of the Pacific--moves moisture to the east across the ocean and away from the western Unites States. As a result, the air is deprived of moisture when the subtropical high pressure hunkers down over the state for the spring and pre-monsoon summer, dry heat results. The La Niña effect, essentially the opposite of El Niño, brings cooler air, often moist cool air, from the northern Pacific via the Pacific, and sometimes Polar, jet streams. This pattern, however, is usually held north of Arizona by the subtropical high pressure, and does not reach into the state to cool the air or cause precipitation.
14. Why does Charleston have higher winter temperatures than Atlanta? The ocean currents for south Carolina are probably warm currents that are transporting warmer water poleward. On the other hand, the ocean currents that effect Atlanta are probably cold water currents that are transporting cold water towards the equator. Furthermore, the elevation of south Carolina, being only 3m above sea level will make south Carolina overall warmer as it effects the amount of moisture and humidity the air can hold. With Atlanta being at 104m above sea level it is always going to be naturally colder than Charleston 15. The examples above suggest that the influence of warm and cold currents on temperature varies seasonally. Explain this relationship Oceans and air currents transfer heat to one another. Ocean currents depend on the temperatures of the air, gravity, tides, the salt-content (density) of the water itself, and as always, carbon dioxide levels (in both the water and air). One interruption to the ocean currents could have an enormous impact on the climate. Such things triggered many ice ages
in the past. So as such the temperature of the air in its manifestation as seasons will have an effect on the current circulation by changing the temperature of the current circulation. 16. Compare the precipitation amounts between Los Angeles and Charleston. Explain how ocean currents affect evaporation rates and stability, contributing to the precipitation differences If these currents are warm, there is more evaporation into the air. This is why Los Angeles classified as a marine climate, has less rain. Furthermore the summers and winters in Los Angeles will be mild. The precipitation of Los Angeles is determined by the advection of air over ocean currents to land. When cool water is upwind the summer high temperatures are held down. This contributes to stability in the annual range of temperature. Warmer ocean currents upwind lead to milder winter temperatures making snowfall rare. If the moistureladen air is carried over the mainland, it brings a chance of rain. The more moisture in the air, the greater is the chance of rain. The ocean currents don’t affect climate directly. Rain over the land requires winds (which are linked with pressure systems) to be blowing in the right direction to bring moisture bearing clouds over the land. However, ocean currents are extremely influential, as the effects of El Niño have shown. The opposite applies with cold ocean currents. There is less evaporation, so the air rising over the mainland is less moist and there is less chance of rainfall. Charleston, located on the east coast and having Humid Subtropical climate places it near the source region for maritime tropical air. Additionally, warm ocean currents paralleling these coasts further enhance the instability of the air. These factors combine to produce moderate amounts of precipitation in most months of the year. The humid subtropical climate is subject to cold temperatures during the winter as cP air masses embedded in cyclonic storms pass through this region. 17. What causes the rainy and dry seasons in Dakar Dakar is at 14°N latitude, so it is natural for it to have wet summers and dry winters. rainy seasons, are a shift in wind direction which causes excessive rainfall in many parts of the world including Asia, North America, South America, and Africa. The primary mechanism behind a monsoon is a shift in global wind patterns. During most of the year, winds blow from land to ocean making the air dry. Winds originating from land are called continental. During certain months of the year, the winds begin to blow from the ocean to the land making the air moist. Winds originating over a body of water are called maritime. This moist ocean air is what causes monsoonal rains over many countries. During the summer months in Senegal the wind shifts, and begins blowing towards the land which creates a rainy season.
18. Explain why Rome has a rainy and a Dry season During summer, regions of Mediterranean climate are dominated by subtropical high pressure cells, with dry sinking air capping a surface marine layer of varying humidity and making rainfall impossible or unlikely except for the occasional thunderstorm, while during winter the polar jet stream and associated periodic storms reach into the lower latitudes of the Mediterranean zones, bringing rain, with snow at higher elevations. As a result, areas with this climate receive almost all of their yearly rainfall during their winter season, and may go anywhere from 4 to 6 months during the summer without having any significant precipitation.
19. Explain how sub-tropical high contributes to summer dryness in Los Angeles. How does sub-tropical high pressure contribute to the very different summer precipitation pattern at Charleston Sub-tropical High pressure systems are frequently associated with light winds at the surface and subsidence through the lower portion of the troposphere. In general, subsidence will dry out an air mass by adiabatic, or compressional, heating, thus the summer in Los Angeles, when wind is less frequent is very dry. In Charleston the climate is defined as humid subtropical, so the high pressure system will be very humid. The humid conditions keep the low temperatures in the evening from getting very cool. Summer precipitation in Charleston will be associated with convection.
