Climatic Change - SS3 Geography Past Questions and Answers - page 2

The greenhouse effect is a natural process where certain gases (greenhouse gases) in the Earth's atmosphere trap heat from the sun, keeping the planet warm. The main greenhouse gases include carbon dioxide (CO2), methane (CH4), and water vapor (H2O). However, human activities have increased the concentration of these gases, intensifying the greenhouse effect and causing global warming and climate change.

The submergence of coastal cities due to rising sea levels can have several long-term effects. It can lead to the displacement of populations, loss of infrastructure, damage to ecosystems, and increased risks of coastal flooding and erosion. 

Plate tectonics, the movement of Earth's tectonic plates, can influence climate by affecting ocean currents, mountain formation, and the distribution of landmasses. For example, the collision of plates can create mountain ranges, which alter wind and rain patterns. The separation of continents can impact ocean currents, leading to changes in climate over geological timescales.

Rising temperatures and prolonged droughts can have adverse effects on agriculture and food security. They can reduce crop yields, lead to water scarcity for irrigation, and disrupt the growth of vital crops. This, in turn, can cause food shortages, increase food prices, and affect the livelihoods of farming communities.

When ice caps melt, they contribute to rising sea levels. This, in turn, can result in coastal flooding and erosion. Coastal areas may become uninhabitable, impacting communities and ecosystems. Furthermore, saltwater intrusion can contaminate freshwater sources, affecting water supplies and agriculture.