Global surface temperatures have increased 0.6—1.2 degrees since the late 19th century. The 20th century’s 10 warmest years all happened within the last 15 years. Of these,1998 was the warmest year on record. The snow covering the Northern Hemisphere（半球）and floating ice in the Arctic Ocean decreased. Globally, sea level has risen 4—10 inches over the past century. World-wide amount of rain and snow over land has increased by about one percent. The number of major rainfall events has increased throughout much of the United States.
Increasing concentrations（集中）of greenhouse gases are likely to make climate change faster. Scientists expect that the average global surface temperature could rise 1.6—6.3 degrees by 2100，and the climate in different areas could change differently. Evaporation（蒸发）will increase as the climate warms, which will increase average global amount of rain and snow. Soil moisture（潮湿）is likely to decrease in many areas, and strong rainstorms are likely to become more frequent.Sea level is likely to rise two feet along most of the U.S coast.
Calculations of climate change for certain areas are much less able to be trusted than global ones, and it is unclear whether the climate in different areas will become more variable（变化无常的）.
64．Which of the following statements is not mentioned in the first paragraph?
A．The snow has been seen covering the Southern Hemisphere .
B．More and more major rainfall events have happened to the U.S.
C．On the whole earth, sea level has risen 4—10 inches.
D．The amount of the rain in the world has increased by about 1%.
65．According to scientists, the reason why the climate becomes warm is that________.
A．the snow covering Northern Hemisphere has decreased
B．evaporation has increased in the recent years
C．greenhouse gases concentrate increasingly
D．the floating ice in the Arctic Ocean has decreased
66．It is because______ that strong rainstorms become more frequent.
A．average global little of rain and snow increases
B．the climate becomes warm
C．soil moisture decreases
D．sea level rises two feet
