Summary of knowledge points in the first volume of seventh grade geography

In this article, I summed up the important knowledge points of the first volume of the seventh grade geography, hoping to help students systematically review the geography knowledge of the first volume of the seventh grade.

Earth and map 1. The shape and size of the earth

The earth is a sphere.

(2) The fleet led by Portuguese navigator Magellan realized the first voyage around the earth.

(3) The surface area of the earth is 5 1 10,000 square kilometers, the maximum circumference is 40,000 kilometers, the equatorial radius is 6,378 kilometers, the polar radius is 6,357 kilometers, and the average radius is 637 1 kilometer.

2. Weft and warp yarns

(1) Latitude: a circle perpendicular to the earth axis and surrounding the earth.

Latitude varies in length, and the equator is the largest latitude circle.

(2) Meridian: a semicircle connecting the north and south poles and intersecting the latitude vertically.

The warp is equal in length.

3. Latitude and longitude

(1) Latitude variation law: increasing from equator (0 latitude) to north and south poles. The maximum latitude is 90 degrees, at the South Pole and the North Pole.

(2) The latitude north of the equator is called north latitude, which is represented by "n"; The latitude south of the equator is called the southern latitude, which is represented by "S".

(3) With the equator as the boundary, the earth is divided into two hemispheres, with the northern hemisphere in the north and the southern hemisphere in the south.

(4) Longitude variation law: increasing from the prime meridian (0 meridian) from west to east to 180.

(5) The longitude east of the prime meridian is called east longitude, which is represented by "e"; The longitude west of the prime meridian is called the west longitude, which is expressed by "W".

(6) The dividing line between the eastern hemisphere and the western hemisphere is the warp circle consisting of 20 W and160 E. ..

The west of 20 w to160 e belongs to the western hemisphere (greater than 20 w or160 e).

East of 20 W to160 E belongs to the Eastern Hemisphere (less than 20 W or less than160 E).

Autobiography and the revolution of the earth 1. earth rotation

(1) Meaning: The earth keeps spinning around its axis.

(2) Direction: from west to east.

(3) Cycle: one day (about 24 hours).

(4) Phenomenon: alternating day and night, local time difference.

2. The revolution of the earth

(1) Meaning: The earth moves around the sun.

(2) Direction: from west to east.

(3) Cycle: one year (about 365 days).

(4) Features: The included angle between the orbital plane of the earth and the earth axis is 66.5.

(5) Phenomenon:

① The direct point of the sun moves back and forth between the Tropic of Cancer;

(2) the change of solar altitude angle at the same location;

③ the change of the length of day and night in the same place;

④ In the same place, the light and heat of the sun are different in different seasons, that is, the formation of the four seasons.

Weather and temperature 1. Weather has two important characteristics: weather reflects the atmospheric conditions in a short time; At the same time, the weather in different places may be very different.

2. See Figure 3.4 on page 45 of the textbook for wind direction and wind force.

3. Temperature and its distribution

① The highest temperature in a day appears around 2 pm, and the lowest temperature appears around sunrise.

② In a year, the temperature in the northern hemisphere is the highest in July and the lowest in 65438+ 10.

In a year, the temperature in the southern hemisphere is the lowest in July, and the temperature in the mainland is the highest in 65438+ 10.

③ From the equator to the poles, the temperature gradually decreases.

(4) According to the observation, the temperature drops by about 0.6℃ every time the altitude rises 100 meters.

⑤ Use isotherm diagram to show the horizontal distribution of air temperature.

4. Precipitation and its distribution

① Rain, snow and hail falling from the atmosphere are collectively referred to as precipitation. Rainfall is the main form of precipitation. ② From the equator to the poles, the general trend is that the annual precipitation decreases gradually.

③ Near the Tropic of Cancer, there is more precipitation on the east coast of the mainland and less precipitation on the west coast of the mainland.

④ In temperate regions, there is less precipitation in Chinese mainland and more precipitation in coastal areas.

⑤ The distribution of precipitation is represented by isoprecipitation line graph.

6. The world's "rainy pole"-begging for help; The world's "dry pole"-Atacama Desert.

⑦ Usually, there is more precipitation on windward slopes and less precipitation on leeward slopes in mountainous areas.

4. World climate

(1) Climate is the average weather condition of a place for many years, and generally it doesn't change much.

② Near the equator (tropical rain forest climate); Polar regions (frigid climate); The east coast of the mainland near the Tropic of Cancer (subtropical monsoon and monsoon humid climate); The west coast of the mainland near the Tropic of Cancer (tropical desert climate); Mid-latitude inland areas (temperate continental climate).

③ Climatic characteristics of tropical rain forest: high temperature and rainy all year round; Mediterranean climate features: less rain in high temperature period and more rain in low temperature period.

④ The main factors affecting climate are latitude, land and sea, topography, temperature and precipitation.