Climate change could affect food supplies, water resources, human health and homes.

If greenhouse gas emissions keep increasing at the current rate, global temperature is expected to rise between 2°C and 6°C by 2100. This doesn’t sound much, but a 5°C change is the difference between the current warm period and an ice age. 

Global warming leads to other changes in the climate: melting ice, more evaporation(蒸发), changes in geographical patterns of rainfall, heavier downpours separated by longer dry spells, more frequent heat waves, more intense hurricanes, and sea level rise. 

These changes could affect crop growth as drought, increased evaporation and shrinking glaciers（冰川）disrupt water supply. Some crops could suffer heat stress. While there may be benefits in some regions, overall climate change is likely to have a negative impact on global food supplies. The impacts of climate change on agriculture will vary widely around the world. A global temperature rise of 1–2 °C is expected to increase food production in some regions, particularly mid-latitude areas. But in tropical regions even a small amount of warming could reduce crop yields. A temperature rise of 3 °C or more could threaten global food resources, as all regions are likely to experience negative impacts overall.

Freshwater resources could also diminish, especially in tropical regions, as rain patterns change and evaporation speeds up. Some communities could lose essential melt water as glaciers disappear, while more intense rainfall and hurricanes could cause more flooding, leading to water pollution and bacterial diseases such as cholera（霍乱）becoming more widespread. 

Climate change could lead to a variety of health impacts – both positive and negative. On the negative side, scientists anticipate more cases of malnutrition, heatstroke and waterborne diseases such as cholera. Although some populations will benefit from a reduced risk of cold-related illnesses such as hypothermia, overall a warming world is likely to have negative effects on human health.

Scientists also expect damage to homes and buildings from more intense hurricanes, heavier rainfall and rising sea levels. Climate change is likely to affect infrastructure by increasing the risk of both coastal and inland flooding around the world, owing to a combination of heavier rainfall, rising sea levels and increased storm damage. Homes and buildings could also be affected by the thawing of frozen ground and greater risk of forest fires.

The consequences of climate change will have an impact on people around the world.

小题1:With global temperature increased by 1–2 °C, _______.

A．crops yields could be increased in tropical regions

B．food production could rise throughout the world

C．chances are that food resources would be threatened overall

D．mid-latitude areas are likely to experience positive impacts小题2:The underlined word “hypothermia” in Paragraph 6 possibly means a serious medical condition caused by_______.

A．lower temperature than normal

B．higher temperature than normal

C．more cases of malnutrition

D．cases of waterborne diseases小题3:According to the passage, climate change has both positive and negative effects on ______.

A．food supplies and buildings

B．freshwater resources and homes

C．human health and food supplies

D．human health and homes小题4:The passage is mainly meant to tell us _______.

A．how global warming leads to changes in the climate

B．how climate change affects people worldwide

C．why climate change affects our crop growth

D．why climate change contributes to all bad results