Climatology: UPSC Previous Year Questions (Geography)

Explanation

Tropical rainforests, also called equatorial forests, are found near the equator between the Tropics of Cancer and Capricorn. These forests thrive in areas with high temperatures and consistent rainfall, which support the rich and diverse vegetation.

Statement 1 is correct: This is a defining characteristic of tropical rainforests, also called equatorial forests. The trees are generally tall (often reaching 30-45 meters), and their crowns form a continuous canopy, which allows very little sunlight to reach the forest floor. The canopy helps in conserving moisture and maintaining the unique ecosystem.

Statement 2 is correct: Tropical rainforests are known for their high biodiversity, with a large number of species coexisting in close proximity. The climatic conditions (constant warmth and moisture) lead to intense ecological dynamics that promote coevolution, making these forests the most biodiverse terrestrial ecosystems on Earth.

Statement 3 is correct: Epiphytes, such as mosses, ferns, and orchids, are common in equatorial forests. These plants grow on other plants (usually trees) to reach sunlight, without drawing nutrients from the soil. Epiphytes are abundant in the tropics due to the high humidity and constant sunlight.

Explanation

The annual range of temperature refers to the difference between the highest and lowest temperatures over the course of a year. This range is typically higher in the interior of continents compared to coastal areas due to specific climatic factors.

Statement 1 is correct: Land heats and cools more rapidly than water due to its lower specific heat capacity. This leads to greater temperature extremes in continental interiors. In contrast, coastal areas experience moderate temperatures year-round be-cause water’s higher specific heat allows it to absorb and release heat more slowly, stabilizing the climate.

Statement 2 is incorrect: Altitude affects local temperature (higher altitudes are cooler), but it does not significantly influence the annual temperature range between coastal and interior regions. The question is about horizontal (coastal vs. interior) differences, not vertical (altitude) differences.

Statement 3 is incorrect: While winds affect the local temperature, strong winds do not have a direct relationship with the annual temperature range. Wind patterns influence the distribution of temperature but do not necessarily cause a high annual range in the interior of continents.

Statement 4 is incorrect: In fact, coastal areas usually receive more rainfall due to their proximity to large water bodies. Heavy rains tend to moderate temperatures by increasing humidity, which reduces temperature variations. Thus, this is not a factor in increasing the annual temperature range.

Explanation

The description of extreme climate, scanty rain-fall, and nomadic herding best fits the Central Asian Steppe Climate or Temperate Continental Climate or Temperate Grassland Climate:

Temperature: The continental climate of the Steppe regions is characterized by extreme temperature variations between summer and winter. Precipitation: The average rainfall is about 45 cm, but varies as per location from 25 cm to 75 cm. The heaviest rain in June and July (late spring and early summer). Lifestyle: Historically, the Central Asian Steppe was home to nomadic herders like the Kirghiz and Kazakhs, who relied on migratory animal grazing. However, nomadic lifestyles have largely declined due to modernization.

Explanation

Thunder is caused by lightning. When a lightning bolt travels through the air, it heats the air to an extremely high temperature (up to 30,000 Kelvin). This sudden heating causes the air to expand explosively, creating a shockwave that we hear as thunder. It is not caused by the meeting of clouds, the separation of clouds, or the upward movement of air and water particles.

Statement 1 is incorrect: Thunder is not caused by the meeting of clouds. Cumulonimbus clouds are indeed responsible for thunderstorms, but thunder itself results from the rapid heating and expansion of air due to lightning, not the merging of clouds.

Statement 2 is incorrect: Lightning occurs due to electrical dis-charge within or between clouds and the ground. Thunder results from the sudden expansion of air due to the intense heat of lightning, not from nimbus cloud separation.

Statement 3 is incorrect: While violent air and water particle movements occur within cumulonimbus clouds during a thunderstorm, they do not directly produce thunder. The updrafts and downdrafts determine storm intensity but are not responsible for the sound of thunder.