CBSE Class 11 Fundamental of Physical Geography Chapter 12 NCERT Solutions

Solution: Koeppen's 'A' type climates are the Tropical Humid Climates. These are found between the Tropic of Cancer and the Tropic of Capricorn. A key characteristic of these climates is that the mean monthly temperature of all the months is more than 18° C. This high temperature, combined with significant rainfall, defines these tropical regions.

The correct option is (c) Mean monthly temperature of all the months more than 18° C.

Solution: V. Koeppen developed a system for classifying world climates based on observed temperature and precipitation data. This approach, which relies on empirical evidence and statistical relationships between climate and vegetation, is known as an empirical classification. It focuses on the observable characteristics of climate rather than its causes.

The correct option is (d) Empirical.

Solution: India experiences a monsoon type of climate, which is characterized by distinct wet and dry seasons. According to Koeppen's classification, this type of climate, particularly prevalent in the Indian Peninsula with its significant rainfall influenced by monsoonal winds, is designated as 'Am' - Tropical monsoon climate.

The correct option is (d) "Am".

Solution: Scientific records and climate data indicate that the year 1990 was one of the warmest years globally, reflecting the trend of rising global temperatures. While other years like 1998 also showed significant warmth, 1990 is often cited in climate studies as a peak year for global average temperatures.

The correct option is (a) 1990.

Solution: Humid conditions in climate classification are generally associated with ample rainfall throughout the year or significant rainfall periods. In Koeppen's system, the 'A' group (Tropical Humid Climates) and 'C' group (Temperate Humid Climates) typically represent humid conditions. 'D' (Cold Climates) can also have humid periods, and 'E' (Polar Climates) while cold, receive precipitation. The group 'B' (Dry Climates) is characterized by aridity. Therefore, a combination including A, C, D, and E would represent predominantly humid or precipitation-receiving conditions across different temperature regimes.

The correct option is (b) A—C—D—E.

Solution: V. Koeppen used two primary climatic variables for his classification system: mean annual temperature and mean monthly temperature, along with precipitation amounts. These empirical data points were used to define distinct climate zones based on their thermal and moisture characteristics.

Solution: The empirical system of climate classification, like Koeppen's, is based on observed data such as temperature and precipitation. In contrast, a genetic system attempts to classify climates based on their underlying causes, such as atmospheric circulation patterns or the factors that create specific climatic conditions.

Solution: Climates found near the equator, such as the Tropical wet climate (Af), typically exhibit a very low annual range of temperature. In these regions, temperatures remain relatively constant throughout the year, with minimal variation between the hottest and coldest months, due to the consistent direct solar radiation.

Solution: An increase in sunspot activity is often associated with changes in solar radiation reaching Earth. While the exact relationship is complex and debated, some studies suggest that increased sunspots may correlate with cooler and wetter weather conditions globally, potentially leading to greater storminess. Conversely, a decrease in sunspots might be linked to warmer and drier conditions.

Solution:

'A' - Tropical Humid Climates: These climates are located within the tropics, between the Tropic of Cancer and the Tropic of Capricorn. They are characterized by high temperatures throughout the year, with the sun's rays being nearly vertical. The Inter Tropical Convergence Zone (ITCZ) significantly influences these regions, leading to hot and humid conditions. This group is further divided into three subtypes: Af (Tropical wet), Am (Tropical monsoon), and Aw (Tropical wet and dry).

'B' - Dry Climates: These climates are defined by their low rainfall, which is insufficient to support abundant plant growth. They cover extensive areas, typically found between 15° and 60° north and south of the equator. The 'B' group is subdivided into steppe or semi-arid climate (BS) and desert climate (BW). These are further classified into subtropical steppe (BSh) and subtropical desert (BWh) based on their latitudinal position and associated atmospheric conditions.

The fundamental difference lies in moisture availability: 'A' climates are humid and receive significant rainfall, while 'B' climates are arid or semi-arid due to insufficient precipitation.