NCERT Notes: Grade 6 Social Science - Chapter 2: Globe: Latitudes and Longitudes

Introduction

The Earth, our home planet, is vast and diverse. To study and understand it, geographers and navigators use the Globe, a mini representation of Earth, marked with crucial lines called latitudes and longitudes. These lines serve as reference points and play a vital role in determining time, position, and climatic patterns.

Globe: A Model Earth

• Definition: A globe is a spherical model of the Earth. It provides a three-dimensional view of the world, offering a realistic representation of continents, oceans, and lines of latitude and longitude.

• Significance: Globes help in understanding the shape, size, and relative positions of continents and oceans.

Latitudes

Latitudes are the horizontal lines that run from east to west on the globe.

Characteristics of Latitudes

• Equator: The central latitude is called the Equator. It divides the Earth into two halves: the Northern Hemisphere and the Southern Hemisphere.

• Degrees: Latitudes are calibrated in degrees. The Equator is 0°, while the North Pole and South Pole are 90°N and 90°S respectively.

• Purpose: Latitudes help in determining the climate of a place. Areas near the Equator experience tropical climates, while regions near the poles have polar climates.

Longitudes

Longitudes are the vertical lines that run from the North Pole to the South Pole.

Characteristics of Longitudes

• Prime Meridian: The central longitude, passing through Greenwich in London, is termed the Prime Meridian. It’s marked as 0° longitude.

• 180° Meridian: Directly opposite to the Prime Meridian, it’s essential in determining the International Date Line.

• Purpose: Longitudes play a significant role in determining time. With every 15° longitude, there’s a difference of one hour.

Time Zones and Longitudes

• Calculation: Earth takes 24 hours for a complete rotation. With 360° of longitudes, every hour it covers 15°. Hence, time can be determined based on the position of a place on the longitude.

• International Date Line: Located at 180° longitude, it’s a demarcation point where the date changes. Crossing from west to east subtracts a day, while from east to west adds a day.

Significance of Latitudes and Longitudes

1. Navigation: Sailors and pilots use these coordinates to navigate and determine their exact position.

2. Time Determination: As Earth rotates, different parts witness day and night. Longitudes help determine local times of places.

3. Climate Study: Latitude determines the solar energy received, affecting the climate of the regions.

Heat Zones of the Earth

Based on latitudes, Earth is divided into:

• Torrid Zone: Lies between the Tropic of Cancer (23½°N) and the Tropic of Capricorn (23½°S). It’s the hottest region.

• Temperate Zones: Lie between the Tropics and the Arctic and Antarctic Circles. These have moderate temperatures.

• Frigid Zones: Located beyond the Arctic and Antarctic Circles, up to the poles. These zones experience extreme cold.

Conclusion

The globe, with its latitudes and longitudes, is not just a geographical tool but a representation of the interconnectedness of our world. Whether determining time or understanding climatic changes, these lines on the globe play a pivotal role in shaping our understanding of Earth and its myriad mysteries.

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Reference: NCERT Grade 6 Social Science - Chapter 2: Globe: Latitudes and Longitudes

Note: This article offers an SEO-optimized overview of the significance of the Globe, latitudes, and longitudes. For a comprehensive understanding, students should consult the original NCERT textbook.