Soot（烟灰）and Snow: a Hot Combination①New research from NASA scientists suggests emissions（释放）of black soot alter the way sunlight reflects off snow. According to a computer simulation（模拟），black soot may be responsible for 25 percent of observed global warming over the past century.②Soot in the higher latitudes（纬度）of the Earth，where ice is more common，absorbs more of the sun's energy and warmth than an icy，white background. Dark-colored black carbon，or soot，absorbs sunlight，while lighter colored ice reflects sunlight.③Soot in areas with snow and ice may play an important role in climate change. Also，if snow and ice covered areas begin melting，the warming effect increases，as the soot becomes more concentrated on the snow surface. “This provides a positive feedback，as glaciers and ice sheet smelt，they tend to get even dirtier，" said Dr. James Hansen，a researcher at NASA's Goddard Institute for Space Studies，New York.④Hansen found soot’s effect on snow albedo（反照率）（solar energy reflected back to space），which may be contributing to trends toward early springs in the Northern Hemisphere，such as thinning Arctic sea ice，melting glaciers and permafrost（永冻层）.Soot also is believed to play a role in changes in the atmosphere above the oceans and land.⑤”Black carbon reduces the amount of energy reflected by snow back into space，thus heating the snow surface more than if there were no black carbon，"Hansen said. Soot’s increased absorption of solar energy is especially effective in warming the world's climate. “This forcing is unusually effective，causing twice as much global warming as a carbon-dioxide（二氧化物）forcing of the same magnitude（量，大小），”Hansen noted.⑥Hansen cautioned , although the role of soot in altering global climate is substantial , it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century. Such gases are expected to be the largest climate forcing for the rest of this century.⑦The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were consistent with the researchers ' climate model simulations, which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.【第19题】Paragraph④____.A.Soot' s Role in Climate Changes Above Oceans and Land;B.Observations of Warming in the Northern Hemisphere;C.Explanation of Increased Warming Effect Caused by Soot;D.Black Soot in Snow and Icy Areas Leading to Climate Change;E.Black Soot Contributing to Global W arming;F.Greenhouse Gases as the Main Factor of Global Warming

Soot（烟灰）and Snow: a Hot Combination①New research from NASA scientists suggests emissions（释放）of black soot alter the way sunlight reflects off snow. According to a computer simulation（模拟），black soot may be responsible for 25 percent of observed global warming over the past century.②Soot in the higher latitudes（纬度）of the Earth，where ice is more common，absorbs more of the sun's energy and warmth than an icy，white background. Dark-colored black carbon，or soot，absorbs sunlight，while lighter colored ice reflects sunlight.③Soot in areas with snow and ice may play an important role in climate change. Also，if snow and ice covered areas begin melting，the warming effect increases，as the soot becomes more concentrated on the snow surface. “This provides a positive feedback，as glaciers and ice sheet smelt，they tend to get even dirtier，" said Dr. James Hansen，a researcher at NASA's Goddard Institute for Space Studies，New York.④Hansen found soot’s effect on snow albedo（反照率）（solar energy reflected back to space），which may be contributing to trends toward early springs in the Northern Hemisphere，such as thinning Arctic sea ice，melting glaciers and permafrost（永冻层）.Soot also is believed to play a role in changes in the atmosphere above the oceans and land.⑤”Black carbon reduces the amount of energy reflected by snow back into space，thus heating the snow surface more than if there were no black carbon，"Hansen said. Soot’s increased absorption of solar energy is especially effective in warming the world's climate. “This forcing is unusually effective，causing twice as much global warming as a carbon-dioxide（二氧化物）forcing of the same magnitude（量，大小），”Hansen noted.⑥Hansen cautioned , although the role of soot in altering global climate is substantial , it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century. Such gases are expected to be the largest climate forcing for the rest of this century.⑦The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were consistent with the researchers ' climate model simulations, which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.【第20题】Paragraph⑤____.A.Soot' s Role in Climate Changes Above Oceans and Land;B.Observations of Warming in the Northern Hemisphere;C.Explanation of Increased Warming Effect Caused by Soot;D.Black Soot in Snow and Icy Areas Leading to Climate Change;E.Black Soot Contributing to Global W arming;F.Greenhouse Gases as the Main Factor of Global Warming

Soot（烟灰）and Snow: a Hot Combination①New research from NASA scientists suggests emissions（释放）of black soot alter the way sunlight reflects off snow. According to a computer simulation（模拟），black soot may be responsible for 25 percent of observed global warming over the past century.②Soot in the higher latitudes（纬度）of the Earth，where ice is more common，absorbs more of the sun's energy and warmth than an icy，white background. Dark-colored black carbon，or soot，absorbs sunlight，while lighter colored ice reflects sunlight.③Soot in areas with snow and ice may play an important role in climate change. Also，if snow and ice covered areas begin melting，the warming effect increases，as the soot becomes more concentrated on the snow surface. “This provides a positive feedback，as glaciers and ice sheet smelt，they tend to get even dirtier，" said Dr. James Hansen，a researcher at NASA's Goddard Institute for Space Studies，New York.④Hansen found soot’s effect on snow albedo（反照率）（solar energy reflected back to space），which may be contributing to trends toward early springs in the Northern Hemisphere，such as thinning Arctic sea ice，melting glaciers and permafrost（永冻层）.Soot also is believed to play a role in changes in the atmosphere above the oceans and land.⑤”Black carbon reduces the amount of energy reflected by snow back into space，thus heating the snow surface more than if there were no black carbon，"Hansen said. Soot’s increased absorption of solar energy is especially effective in warming the world's climate. “This forcing is unusually effective，causing twice as much global warming as a carbon-dioxide（二氧化物）forcing of the same magnitude（量，大小），”Hansen noted.⑥Hansen cautioned , although the role of soot in altering global climate is substantial , it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century. Such gases are expected to be the largest climate forcing for the rest of this century.⑦The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were consistent with the researchers ' climate model simulations, which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.【第21题】 In the twentieth century , soot_____.A.produces much more global warming than a carbon-dioxide forcing of the same magnitude.;B.contributed to 25 percent of observed global warming;C.winter and spring;D.the warming effects increase .;E. Still surpass soot in warming the world’s climate during the last century;F.can be seen mostly in the Northern Hemisphere

Soot（烟灰）and Snow: a Hot Combination①New research from NASA scientists suggests emissions（释放）of black soot alter the way sunlight reflects off snow. According to a computer simulation（模拟），black soot may be responsible for 25 percent of observed global warming over the past century.②Soot in the higher latitudes（纬度）of the Earth，where ice is more common，absorbs more of the sun's energy and warmth than an icy，white background. Dark-colored black carbon，or soot，absorbs sunlight，while lighter colored ice reflects sunlight.③Soot in areas with snow and ice may play an important role in climate change. Also，if snow and ice covered areas begin melting，the warming effect increases，as the soot becomes more concentrated on the snow surface. “This provides a positive feedback，as glaciers and ice sheet smelt，they tend to get even dirtier，" said Dr. James Hansen，a researcher at NASA's Goddard Institute for Space Studies，New York.④Hansen found soot’s effect on snow albedo（反照率）（solar energy reflected back to space），which may be contributing to trends toward early springs in the Northern Hemisphere，such as thinning Arctic sea ice，melting glaciers and permafrost（永冻层）.Soot also is believed to play a role in changes in the atmosphere above the oceans and land.⑤”Black carbon reduces the amount of energy reflected by snow back into space，thus heating the snow surface more than if there were no black carbon，"Hansen said. Soot’s increased absorption of solar energy is especially effective in warming the world's climate. “This forcing is unusually effective，causing twice as much global warming as a carbon-dioxide（二氧化物）forcing of the same magnitude（量，大小），”Hansen noted.⑥Hansen cautioned , although the role of soot in altering global climate is substantial , it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century. Such gases are expected to be the largest climate forcing for the rest of this century.⑦The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were consistent with the researchers ' climate model simulations, which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.【第22题】 If snow and ice covered areas begin melting, _____.A.produces much more global warming than a carbon-dioxide forcing of the same magnitude.;B.contributed to 25 percent of observed global warming;C.winter and spring;D.the warming effects increase .;E. Still surpass soot in warming the world’s climate during the last century;F.can be seen mostly in the Northern Hemisphere

Soot（烟灰）and Snow: a Hot Combination①New research from NASA scientists suggests emissions（释放）of black soot alter the way sunlight reflects off snow. According to a computer simulation（模拟），black soot may be responsible for 25 percent of observed global warming over the past century.②Soot in the higher latitudes（纬度）of the Earth，where ice is more common，absorbs more of the sun's energy and warmth than an icy，white background. Dark-colored black carbon，or soot，absorbs sunlight，while lighter colored ice reflects sunlight.③Soot in areas with snow and ice may play an important role in climate change. Also，if snow and ice covered areas begin melting，the warming effect increases，as the soot becomes more concentrated on the snow surface. “This provides a positive feedback，as glaciers and ice sheet smelt，they tend to get even dirtier，" said Dr. James Hansen，a researcher at NASA's Goddard Institute for Space Studies，New York.④Hansen found soot’s effect on snow albedo（反照率）（solar energy reflected back to space），which may be contributing to trends toward early springs in the Northern Hemisphere，such as thinning Arctic sea ice，melting glaciers and permafrost（永冻层）.Soot also is believed to play a role in changes in the atmosphere above the oceans and land.⑤”Black carbon reduces the amount of energy reflected by snow back into space，thus heating the snow surface more than if there were no black carbon，"Hansen said. Soot’s increased absorption of solar energy is especially effective in warming the world's climate. “This forcing is unusually effective，causing twice as much global warming as a carbon-dioxide（二氧化物）forcing of the same magnitude（量，大小），”Hansen noted.⑥Hansen cautioned , although the role of soot in altering global climate is substantial , it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century. Such gases are expected to be the largest climate forcing for the rest of this century.⑦The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were consistent with the researchers ' climate model simulations, which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.【第23题】A soot forcing is unusually effective , which_____.A.produces much more global warming than a carbon-dioxide forcing of the same magnitude.;B.contributed to 25 percent of observed global warming;C.winter and spring;D.the warming effects increase .;E. Still surpass soot in warming the world’s climate during the last century;F.can be seen mostly in the Northern Hemisphere

Soot（烟灰）and Snow: a Hot Combination①New research from NASA scientists suggests emissions（释放）of black soot alter the way sunlight reflects off snow. According to a computer simulation（模拟），black soot may be responsible for 25 percent of observed global warming over the past century.②Soot in the higher latitudes（纬度）of the Earth，where ice is more common，absorbs more of the sun's energy and warmth than an icy，white background. Dark-colored black carbon，or soot，absorbs sunlight，while lighter colored ice reflects sunlight.③Soot in areas with snow and ice may play an important role in climate change. Also，if snow and ice covered areas begin melting，the warming effect increases，as the soot becomes more concentrated on the snow surface. “This provides a positive feedback，as glaciers and ice sheet smelt，they tend to get even dirtier，" said Dr. James Hansen，a researcher at NASA's Goddard Institute for Space Studies，New York.④Hansen found soot’s effect on snow albedo（反照率）（solar energy reflected back to space），which may be contributing to trends toward early springs in the Northern Hemisphere，such as thinning Arctic sea ice，melting glaciers and permafrost（永冻层）.Soot also is believed to play a role in changes in the atmosphere above the oceans and land.⑤”Black carbon reduces the amount of energy reflected by snow back into space，thus heating the snow surface more than if there were no black carbon，"Hansen said. Soot’s increased absorption of solar energy is especially effective in warming the world's climate. “This forcing is unusually effective，causing twice as much global warming as a carbon-dioxide（二氧化物）forcing of the same magnitude（量，大小），”Hansen noted.⑥Hansen cautioned , although the role of soot in altering global climate is substantial , it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century. Such gases are expected to be the largest climate forcing for the rest of this century.⑦The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were consistent with the researchers ' climate model simulations, which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.【第24题】 Hansen cautioned that greenhouse gases _____.A.produces much more global warming than a carbon-dioxide forcing of the same magnitude.;B.contributed to 25 percent of observed global warming;C.winter and spring;D.the warming effects increase .;E. Still surpass soot in warming the world’s climate during the last century;F.can be seen mostly in the Northern Hemisphere

Soot（烟灰）and Snow: a Hot Combination①New research from NASA scientists suggests emissions（释放）of black soot alter the way sunlight reflects off snow. According to a computer simulation（模拟），black soot may be responsible for 25 percent of observed global warming over the past century.②Soot in the higher latitudes（纬度）of the Earth，where ice is more common，absorbs more of the sun's energy and warmth than an icy，white background. Dark-colored black carbon，or soot，absorbs sunlight，while lighter colored ice reflects sunlight.③Soot in areas with snow and ice may play an important role in climate change. Also，if snow and ice covered areas begin melting，the warming effect increases，as the soot becomes more concentrated on the snow surface. “This provides a positive feedback，as glaciers and ice sheet smelt，they tend to get even dirtier，" said Dr. James Hansen，a researcher at NASA's Goddard Institute for Space Studies，New York.④Hansen found soot’s effect on snow albedo（反照率）（solar energy reflected back to space），which may be contributing to trends toward early springs in the Northern Hemisphere，such as thinning Arctic sea ice，melting glaciers and permafrost（永冻层）.Soot also is believed to play a role in changes in the atmosphere above the oceans and land.⑤”Black carbon reduces the amount of energy reflected by snow back into space，thus heating the snow surface more than if there were no black carbon，"Hansen said. Soot’s increased absorption of solar energy is especially effective in warming the world's climate. “This forcing is unusually effective，causing twice as much global warming as a carbon-dioxide（二氧化物）forcing of the same magnitude（量，大小），”Hansen noted.⑥Hansen cautioned , although the role of soot in altering global climate is substantial , it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century. Such gases are expected to be the largest climate forcing for the rest of this century.⑦The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were consistent with the researchers ' climate model simulations, which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.【第25题】 Warming in the Northern Hemisphere was large in ____ at middle and high latitudes.A.produces much more global warming than a carbon-dioxide forcing of the same magnitude.;B.contributed to 25 percent of observed global warming;C.winter and spring;D.the warming effects increase .;E. Still surpass soot in warming the world’s climate during the last century;F.can be seen mostly in the Northern Hemisphere

The Disappearing HoneybeeDo you run away when you hear a bee buzzing？Many people do. A bee sting hurts and some people are allergic to bee venom（蜂毒）.But did you know that bees are very important to humans？ Honeybees do more than just make honey. They fly around and pollinate（传授花粉）flowers，plants，and trees.___26___ One third of America's food supply is pollinated by the honeybee.Have you seen or heard a honeybee lately？Bees are mysteriously disappearing in many parts of the world. Most people don't know about this problem. It is called Colony Collapse Disorder（CCD）.Some North American beekeepers lost 80% of their hives（蜂巢）from 2006-2008.___27___The disappearance of the honeybee is a serious problem. Can you imagine never eating another blueberry？What about almonds and cherries？Without honeybees food prices will skyrocket（猛涨）.___28___This problem affects other foods besides fresh produce. Imagine losing your favorite ice cream！ Haagen Daaz is a famous ice cream company. Many of their flavors rely on the hard working honey bee.___29___They also created a website called helpthehoneybee.com.Donating money to research is the most important thing humans can do to save the honeybees. Scientists need money to investigate the causes of Colony Collapse Disorder. Some scientists blame CCD on climate change. Others think pesticides（杀虫剂）are killing the bees.___30___Beekeepers transport their hives from place to place in order to pollinate plants year round.Not everyone has money to donate regularly. There are other ways to help the honeybee. Spread the word，by telling your friends and family about the problem. Tell your teacher about the disappearing bees too. Maybe your class can write a letter to the government.【第26题】根据文章题意，选择对应的句子。A.In 2008 Haagen Daaz began raising money for CCD.;B. It is hard to pin down what has been causing honeybees to vanish.;C.The poorest people always suffer the worst when there is a lack of food.;D.Our fruits，nuts，and vegetables rely on these pollinators.;E.Commercial bee migration may also cause CCD.;F.Bees in Italy and Australia are disappearing too.

The Disappearing HoneybeeDo you run away when you hear a bee buzzing？Many people do. A bee sting hurts and some people are allergic to bee venom（蜂毒）.But did you know that bees are very important to humans？ Honeybees do more than just make honey. They fly around and pollinate（传授花粉）flowers，plants，and trees.___26___ One third of America's food supply is pollinated by the honeybee.Have you seen or heard a honeybee lately？Bees are mysteriously disappearing in many parts of the world. Most people don't know about this problem. It is called Colony Collapse Disorder（CCD）.Some North American beekeepers lost 80% of their hives（蜂巢）from 2006-2008.___27___The disappearance of the honeybee is a serious problem. Can you imagine never eating another blueberry？What about almonds and cherries？Without honeybees food prices will skyrocket（猛涨）.___28___This problem affects other foods besides fresh produce. Imagine losing your favorite ice cream！ Haagen Daaz is a famous ice cream company. Many of their flavors rely on the hard working honey bee.___29___They also created a website called helpthehoneybee.com.Donating money to research is the most important thing humans can do to save the honeybees. Scientists need money to investigate the causes of Colony Collapse Disorder. Some scientists blame CCD on climate change. Others think pesticides（杀虫剂）are killing the bees.___30___Beekeepers transport their hives from place to place in order to pollinate plants year round.Not everyone has money to donate regularly. There are other ways to help the honeybee. Spread the word，by telling your friends and family about the problem. Tell your teacher about the disappearing bees too. Maybe your class can write a letter to the government.【第27题】根据文章题意，选择对应的句子。A.In 2008 Haagen Daaz began raising money for CCD.;B. It is hard to pin down what has been causing honeybees to vanish.;C.The poorest people always suffer the worst when there is a lack of food.;D.Our fruits，nuts，and vegetables rely on these pollinators.;E.Commercial bee migration may also cause CCD.;F.Bees in Italy and Australia are disappearing too.

The Disappearing HoneybeeDo you run away when you hear a bee buzzing？Many people do. A bee sting hurts and some people are allergic to bee venom（蜂毒）.But did you know that bees are very important to humans？ Honeybees do more than just make honey. They fly around and pollinate（传授花粉）flowers，plants，and trees.___26___ One third of America's food supply is pollinated by the honeybee.Have you seen or heard a honeybee lately？Bees are mysteriously disappearing in many parts of the world. Most people don't know about this problem. It is called Colony Collapse Disorder（CCD）.Some North American beekeepers lost 80% of their hives（蜂巢）from 2006-2008.___27___The disappearance of the honeybee is a serious problem. Can you imagine never eating another blueberry？What about almonds and cherries？Without honeybees food prices will skyrocket（猛涨）.___28___This problem affects other foods besides fresh produce. Imagine losing your favorite ice cream！ Haagen Daaz is a famous ice cream company. Many of their flavors rely on the hard working honey bee.___29___They also created a website called helpthehoneybee.com.Donating money to research is the most important thing humans can do to save the honeybees. Scientists need money to investigate the causes of Colony Collapse Disorder. Some scientists blame CCD on climate change. Others think pesticides（杀虫剂）are killing the bees.___30___Beekeepers transport their hives from place to place in order to pollinate plants year round.Not everyone has money to donate regularly. There are other ways to help the honeybee. Spread the word，by telling your friends and family about the problem. Tell your teacher about the disappearing bees too. Maybe your class can write a letter to the government.【第28题】根据文章题意，选择对应的句子。A.In 2008 Haagen Daaz began raising money for CCD.;B. It is hard to pin down what has been causing honeybees to vanish.;C.The poorest people always suffer the worst when there is a lack of food.;D.Our fruits，nuts，and vegetables rely on these pollinators.;E.Commercial bee migration may also cause CCD.;F.Bees in Italy and Australia are disappearing too.