*5.1.3 Sea levels*

*Environmental Issues and Sustainable Development*

Springs occur earlier and winters are milder.

*Climate change is associated with increased Earth's temperature.*

*5.1.2 Mountain glaciers and lakes*

**Figure 2.**

The rise in global mean temperature is not the same everywhere. There are regional variations in Earth's temperature. Some areas will not even get warmer and may actually get cooler in the short term [4]. Warming is more pronounced at higher latitudes. The North Pole and Northern Hemisphere have warmed much faster than the South Pole and Southern Hemisphere. Greater temperature increases are expected in winter compared to summer and in nighttime versus daytime.

Climate change causes mountain glaciers to melt and accelerates the rate of ice loss on Earth in Greenland and Antarctica (**Figure 3**). Some glaciers are sites of

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**Figure 3.**

*Climate change causes melting of mountain glaciers.*

Climate change triggers rise in sea levels. The sea levels rise following either an increase in the volume of the water already in the ocean as water warms and expands or an increase in the mass of the water in the ocean mainly due to melting glaciers [4]. Since 1900, global mean sea level has increased by approximately 0.20 meter [4]. Over the last 25 years, the global mean see level rose on average by 0.003 meter per year [8]. By 2100, based on different emissions scenarios, sea levels are predicted to rise between 0.40 and 1.50 meters [4]. The sea-level rise will lead to disappearance of some islands and flooding with invasion of cities by water, leading to homelessness and population movement (**Figure 4**).

The salty ocean water will challenge native plants and animals to adapt to the changing conditions. For humans, it causes salination of freshwater supplies and loss of productive farmlands [8]. Low-income countries (e.g., Bangladesh) are particularly impacted.

**Figure 4.** *Climate change triggers rise in sea levels.*
