MA. RACHEL B. ESPINOTeacher I, ScienceBuhatan NHS; Sorsogon City

GRADE 9, MODULE 3 LESSON 2.1(Teachers Guide for Discussion)

What is Climate?Climate is the average weather in a particular region over a fairly long period of time.

Climate are affected by four factors:1. Latitude 2. Altitude 3. Distance from bodies of water 4. Ocean currents 5. Topography

What factors affect the average temperature in a given place?

1. The amount of solar radiation receivedfrom the sun is determined by two factors: (a)the angle at which the sun’s rays strike theearth, and (b) the length of time in which thesun shines during a particular day. In turn,these two depend on the latitude of aparticular place (the latitude of an area is itsdistance from the equator).

Direct rays of the sun deliver more heat thanslanted rays. Regions near the equator (low latitude)receive direct rays of the sun throughout the yearand therefore have higher average temperaturecompared to regions near the poles (high latitude),which receive slanted rays. Also, the days and nightsnear the equator are almost equal in length whilenear the poles, the length of days and nights varieswith the season. Toward the pole, the nights arelong in winter while in summer, daylights are long.Thus, the lower the latitude, the warmer theclimate; the higher the latitude, the colder theclimate.

2. The altitude (height above sea level) of a place alsodetermines its climate. Even places near the equatorexperiences a cold climate if they are located at a highaltitude compared to those located at sea level.Example, Baguio City has lower average temperatureand colder climate than the surrounding area becauseof its high altitude.

3. The presence of land and water masses affect theclimate of a place. Since land surfaces heat and coolfaster than water surfaces, land regions experiencehotter summers and colder winters compared to searegions in the same latitude.

4. Mountains and plains determine how distantwinds affect the climate of a region.

The direction of prevailing winds can cause coolsummer and mild winters along the sea coast.

What factors affect the average rainfall in a given place?

1. Like temperature, rainfall is also affected bylatitude. Regions where warm, moist wind rise suchas in the doldrums (area north of equator; an areawith no wind or light variable winds just north of theequator in the Atlantic and Pacific oceans, situatedbetween the trade winds) have heavy rainsthroughout the year. Regions in the traders and lowlatitude are mostly dry while those in the prevailingeasterlies have moderate rainfall all year.

2. Seasonal winds, called monsoons may bring rainyweather during some months and dry weather inother months.

NORTHEAST MONSOON (AMIHAN) SOUTHEAST MONSOON (HABAGAT)December to January July to September

3. Mountains affect the amount of rainfall a givenregion will get. When warm moist wind strike thewindward side of a mountain and rise, there will bemuch rainfall on that side. The opposite side willhave correspondingly little rain (leeward).

4. When winds blow in from the ocean, the regionnearest the ocean gets the most rainfall. Thewarmer the ocean, the heavier the rainfall.

These climates are located within 30° above and below the equator. Here, the sun is nearly always overhead at noon. Tropical climates are therefore the warmest all the year. In the belt of the doldrums, rain is abundant all year. The climates included in this area are (1) tropical rain forest, (2) savannah, (3) tropical desert and (4) tropical steep

These climates are located between 30° and 65° latitude.There us a wide range of temperatures with at least one monthwhere the average temperature is 10°C or higher. A variety ofweather is produced because it is in the belt of the westerlies.The middle-latitude climates are (1) mediterranean, (2) humidsubtropical, (3) marine west coast, (4) humid continental, (5)dry continental and (6) subartic.

Close to the poles the sun is not seen during the winter during the winter for as long as six months. In summary, the sun’s rays that reach it are greatly slanted and therefore have less heat. This region has less precipitation. The climates are (1) tundra and (2) ice cap

Two pronounced seasons: dry from November to April and wet during the rest of the year. The regions located on the western part of Luzon, Mindoro, Negros and Palawan.

No dry season; with a very pronounced maximum rain period from November to April. Regions that have type II climate are Catanduanes, Sorsogon, eastern Albay, eastern and northern CamarinesNorte and CamarinesSur, eastern Mindanao, eastern Quezon and Samar.

Seasons are not very pronounced; relatively dry from November to April and wet during the rest of the year. The regions with this type of climate are the western parts of Cagayan, Isabela, Nueva Vizcaya, the eastern portion of the Mountain Provinces, Southern Quezon, Masbate, Romblon, Northeast Panay, EasternNegros, Central and Southern Cebu, part of Northern Mindanao, and part of Eastern Palawan.

Rainfall more or lessevenly distributedthroughout the year. Theregions with this type ofclimate are Batanes,North-eastern Luzon,South-western CamarinesNorte, WesternCamarines Sur and Albay,Bondoc Peninsula, EasternMindoro, Marinduque,Western Leyte, NorthenCebu, Bohol and most ofcentral, eastern andsouthern Mindanao.

What are the prevailing wind systems over the Philippines

Land and water surfaces differ in their rate ofcooling. Land heats and cools more rapidlythan water. This particularly evident inextensive surfaces. Continents heat and coolfaster than oceans. As a result, a center oflow pressure develops over the continentwhile high pressure develops over theadjacent ocean.

These difference in temperature and pressurebetween continents and oceans broughtabout by changes in the seasons developwind system known as seasonal winds ormonsoons. In summer, the land is heatedmore than the ocean so the cooler air fromthe ocean moves toward the land. In winter,the land gets colder than the ocean so thecooler air from the land moves toward theocean.

What are the prevailing wind systems or monsoons in the Philippines?

In the Northern Hemisphere, a high pressurearea develops over India and Southern Siberiain winter because of the colder air over them.The mass of cold air then moves toward thePacific Ocean. It reaches the Philippines froma north-easterly direction and the air mass iscalled the Northeast Monsoon (Amihan) forthat reason. This prevails the cold morningexperienced in the country from December toFebraury.

NORTHEAST MONSOON (AMIHAN)December to January

During summer in the Northern Hemisphere,the Asian continent becomes warmer thanthe oceans surrounding it. A cold air massdevelops over the Pacific Ocean and begins tomove toward the Asian continent. This formsthe Southwest Monsoon (Habagat) whichprevails over the Philippines in the months ofJuly, August and September.

SOUTHEAST MONSOON (HABAGAT)

July to September

The trade winds, which are the prevailingwinds in the tropics likewise affect thePhilippines during the rest of the year andwhenever the Northeast Monsoon andSouthwest Monsoon weaken.

Basics of Geography: Climate (Shows a simple explanation about climate through animation) http://youtu.be/95TtXYjOEv4

Five Factors that Affect Climate http://youtu.be/E7DLLxrrBV8?list=PLEDBEF577E57

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