Encyclopedia of natural science knowledge for children

Chapter 1

1. The movement pattern of the direct sun point. The direct sun point moves back and forth between the Tropic of Cancer and the Tropic of Cancer in a one-year cycle.

2. Dawn and dusk The line is judged along the direction of rotation. The transition from night to day is the morning line, and the transition from day to night is the dusk line.

3. When calculating local time, for every 1° eastward, the time increases by 4 minutes.

4. If the longitude is known, find the time zone number and divide the longitude by 15, then round off.

5. The calculation of zone time increases by 1 hour for every time zone eastward.

6. Beijing time is based on the East Eighth District (120°E local time) as the standard time.

7. Universal Time: The prime meridian time is used as the standard time.

8. The International Date Line is 180° longitude (theoretically) and does not pass through land (actually).

9. The geographical significance of the earth’s rotation: the change of day and night, time in different places, the deviation of horizontally moving objects (north, right, south, left)

10. The judgment of the direct sun point and the The tangent direction of the point is vertical, and the local time is 12 o'clock.

11. On the vernal equinox (March 21), the sun’s direct point is at the equator, and the twilight line coincides with the longitude.

12. On the summer solstice (June 22), the direct point of the sun is at the Tropic of Cancer, and the twilight line intersects the longitude.

13. On the Autumnal Equinox (September 23), the sun’s direct point is at the equator, and the twilight line coincides with the longitude.

14. On the winter solstice (December 22), the direct point of the sun is at the Tropic of Cancer, and the twilight line intersects the longitude.

15. The concept of the summer half of the year: March 21 to September 23

Part 2

1. The concept of the winter half of the year: September 23 Until March 21st

2. Interpretation of the side view of the Earth: up, north, down, south, left, west, right, east.

3. Interpretation of the top view of the Earth. The Earth rotates counterclockwise, with the North Pole in the center; it rotates clockwise, with the South Pole in the center.

4. Calculation of the length of day and night: Based on the length of the day arc, every 15 degrees is one hour.

5. Calculation of sunrise and sunset times; calculated based on day length based on standard sunrise (6 o'clock) and standard sunset (18 o'clock).

6. Judgment of day and night length: In the summer half of the year, the days are longer in the north, and in the winter half of the year, the days are longer in Vietnam.

7. Calculation of the height of the sun at noon = 90°-(the latitude distance between the direct point and the point being sought)

8. Astronomical seasons: the longest day in a year, the season of the sun It's summer.

9. my country’s traditional four seasons: The four seasons are divided from the beginning of spring (February 4), the beginning of summer, the beginning of autumn, and the beginning of winter.

10. The traditional European and American four seasons: the spring equinox, summer solstice, autumnal equinox, and winter solstice are the starting points of the four seasons.

11. The twenty-four solar terms: spring rain shocks spring, clear valley, sky is full of awns, summer and heat are connected, autumn is dew, autumn is cold and frost falls, winter is snowy and winter is small and cold

12. The names and scope of the five belts : Tropical zone, north temperate zone, south temperate zone, north frigid zone, south frigid zone.

13. The geographical significance of the earth’s revolution: changes in the height of the sun at noon, changes in the length of day and night, and the change of seasons

14. The importance of the atmosphere to the earth protects the survival of living things and affects the earth Natural environment, life-sustaining activities

15. The composition of the lower atmosphere: dry air, water vapor and solid impurities

Part 3

1. The composition of dry air Composition: Nitrogen and oxygen, carbon dioxide and ozone

2. The role of oxygen, nitrogen, ozone, carbon dioxide, water vapor and dust, life activities; forming living organisms; absorbing ultraviolet rays; photosynthesis, heat preservation; forming clouds and causing rain

3. The "greenhouse effect" of atmospheric pollution carbon dioxide, chlorofluorocarbons destroy the ozone layer

4. Vertical stratification of the atmosphere: troposphere, stratosphere (ozone layer), upper atmosphere (ionosphere) )

5. The main characteristics of the troposphere: cold at the top and hot at the bottom, significant convection, and complex and changeable weather phenomena. The closest relationship with humans.

6. The main characteristics of the stratosphere: Ozone absorbs ultraviolet rays. Advection is beneficial to high-altitude flight.

7. The upper boundary of the atmosphere is about 2,000-3,000 kilometers above the ground.

8. The most important factor affecting the intensity of solar radiation: solar altitude angle

9. The weakening effect of the atmosphere on solar radiation: absorption, reflection, and scattering.

10. Radiation Law: The higher the temperature of a substance, the shorter the wavelength of the radiation; vice versa, the longer it is.