[A] snow [B] earth [C] room [D] ice

[A] snow [B] earth [C] room [D] ice


相关考题:

– It’s starting to snow. – Starting to snow?(). (A) They are ready for the snow(B) It is typical December weather(C) Once it starts, it’ll snow a lot(D) It has been snowing for some time

The road was so slippery when the snow was frozen into ice that I nearly _________ down the mountain slope. A.tumbledB.slidC.walkedD.stumbled

The inside of the earth is very, very ____. The rock has melted like ice. A.deepB.coldC.hardD.hot

If a piece of ice is taken into a warm room, it will soon() water. A.turn offB.turn downC.turn intoD.turn on

____ is covered with heavy snow. A.The earth's surfaceB.The surface of earthC.The surface earthD.The earth surface

Widely spaced isobars on a weather map indicate ______.A.High windsB.Gentle breezesC.Ice,snow or frozen rainD.Probability of tornados

共用题干Climate Change:The Long Reach1.Earth is warming.Sea levels are rising.There's more carbon in the air,and Arctic ice is melting faster than at any time in recorded history.Scientists who study the environment to better gauge(评估) Earth's future climate now argue that these changes may not reverse for a very long time.2.People burn fossil fuels like coal and oil for energy.That burning releases carbon dioxide,a colorless gas.In the air,this gas traps heat at Earth's surface.And the more carbon dioxide released,the more the planet warms.If current consumption of fossil fuels doesn't slow,the long-term climate impacts could last thousands of years-and be more severe than scientists had been expecting.Climatologist Richard Zeebe of the University of Hawaii at Manoa offers this conclusion in a new paper.3.Most climate-change studies look at what's going to happen in the next century or so.During that time , changes in the planet's environment could nudge(推动)global warming even higher.For example, snow and ice reflect sunlight back into space.But as these melt,sunlight can now reach-and warm-the exposed ground.This extra heat raises the air temperature even more,causing even more snow to melt.This type of rapid exaggeration of impacts is called a"fast feedback".4.Zeebe says it's important to look at fast feedbacks.However,he adds,they're limited.From a climate change perspective,"This century is the most important time for the next few generations,"he told Science News."But the world is not ending in 2100."For this new study,Zeebe now focuses on"slow feedbacks".While fast feedback events unfold over decades or centuries,slow feedbacks can take thousands of years.Melting of continental ice sheets and the migration of plant life-as they relocate to more comfortable areas-are two examples of slow feedbacks.5.Zeebe gathered information from previously published studies investigating how such processes played out over thousands of years during past dramatic changes in climate.Then he came up with a forecast for the future that accounts for both slow and fast feedback processes.Climate forecasts that use only fast feedbacks predict a 4.5 degree Celsius(8.1 degree Fahrenheit)change by the year 3000.But slow feedbacks added another 1.5℃-for a 6℃ total increase,Zeebe reports.He also found that slow feedback events will cause global warming to persist for thousands of years after people run out of fossil fuels to burn.Arctic ice has never been melting so fast in______.A:the extra heatB:rapid exaggeration of impactsC:the exposed groundD:recorded historyE:a very long timeF:previously published studies

共用题干Climate Change:The Long Reach1.Earth is warming.Sea levels are rising.There's more carbon in the air,and Arctic ice is melting faster than at any time in recorded history.Scientists who study the environment to better gauge(评估) Earth's future climate now argue that these changes may not reverse for a very long time.2.People burn fossil fuels like coal and oil for energy.That burning releases carbon dioxide,a colorless gas.In the air,this gas traps heat at Earth's surface.And the more carbon dioxide released,the more the planet warms.If current consumption of fossil fuels doesn't slow,the long-term climate impacts could last thousands of years-and be more severe than scientists had been expecting.Climatologist Richard Zeebe of the University of Hawaii at Manoa offers this conclusion in a new paper.3.Most climate-change studies look at what's going to happen in the next century or so.During that time , changes in the planet's environment could nudge(推动)global warming even higher.For example, snow and ice reflect sunlight back into space.But as these melt,sunlight can now reach-and warm-the exposed ground.This extra heat raises the air temperature even more,causing even more snow to melt.This type of rapid exaggeration of impacts is called a"fast feedback".4.Zeebe says it's important to look at fast feedbacks.However,he adds,they're limited.From a climate change perspective,"This century is the most important time for the next few generations,"he told Science News."But the world is not ending in 2100."For this new study,Zeebe now focuses on"slow feedbacks".While fast feedback events unfold over decades or centuries,slow feedbacks can take thousands of years.Melting of continental ice sheets and the migration of plant life-as they relocate to more comfortable areas-are two examples of slow feedbacks.5.Zeebe gathered information from previously published studies investigating how such processes played out over thousands of years during past dramatic changes in climate.Then he came up with a forecast for the future that accounts for both slow and fast feedback processes.Climate forecasts that use only fast feedbacks predict a 4.5 degree Celsius(8.1 degree Fahrenheit)change by the year 3000.But slow feedbacks added another 1.5℃-for a 6℃ total increase,Zeebe reports.He also found that slow feedback events will cause global warming to persist for thousands of years after people run out of fossil fuels to burn.Melting of snow and ice enables sunlight to reach______.A:the extra heatB:rapid exaggeration of impactsC:the exposed groundD:recorded historyE:a very long timeF:previously published studies

共用题干Europa's Watery UnderworldEuropa,one of Jupiter's 63 known moons,looks bright and icy on the surface.But appearances can be deceiving:Miles within its cracked,frigid shell,Europa probably hides giant pools of liquid water. Where scientists find liquid water,they hope to find life as well.Since we can't go diving into Europa's depths just yet,scientists instead have to investigate the moon's surface for clues to what lies beneath.In a new study,scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U.S.Great Lakes.Pictures of Europa,which is slightly smaller than Earth's moon,clearly show a tangled,icy mishmash of lines and cracks known as"chaos terrains".These chaotic places cover more than half of Europa. For more than 10 years,scientists have wondered what causes the formations.The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface.For scientists who suspect that Europa also may be hiding life beneath its icy surface,the news about the new lake is exciting."It would be great if these lakes harbored life,"Britney Schmidt,a planetary scientist who worked onthe study,told Science News."But even if they didn't,they say that Europa is doing something interesting and active right now."Schmidt,a scientist at the University of Texas at Austin,and her colleagues wanted to know how chaos terrains form.Since they couldn't rocket to Europa to see for themselves,they searched for similar forma- tions here on Earth.They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice.The scientists now suspect something similar might be happening on Europa:that as water and ice of different temperatures mingle and shift,the surface fractures.This would explain the jumbled ice sculptures."Fracturing catastrophically disrupts the ice in the same way that it causes ice shelves to collapse on Earth,"Schmidt told Science News.She and her team found that the process could be causing chaos terrains to form quickly on Europa.The new study suggests that on this moon,elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life.Schmidt and her colleagues are the first group of scientists reaching Europa.A:RightB:WrongC:Not mentioned

共用题干Europa's Watery UnderworldEuropa,one of Jupiter's 63 known moons,looks bright and icy on the surface.But appearances can be deceiving:Miles within its cracked,frigid shell,Europa probably hides giant pools of liquid water. Where scientists find liquid water,they hope to find life as well.Since we can't go diving into Europa's depths just yet,scientists instead have to investigate the moon's surface for clues to what lies beneath.In a new study,scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U.S.Great Lakes.Pictures of Europa,which is slightly smaller than Earth's moon,clearly show a tangled,icy mishmash of lines and cracks known as"chaos terrains".These chaotic places cover more than half of Europa. For more than 10 years,scientists have wondered what causes the formations.The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface.For scientists who suspect that Europa also may be hiding life beneath its icy surface,the news about the new lake is exciting."It would be great if these lakes harbored life,"Britney Schmidt,a planetary scientist who worked onthe study,told Science News."But even if they didn't,they say that Europa is doing something interesting and active right now."Schmidt,a scientist at the University of Texas at Austin,and her colleagues wanted to know how chaos terrains form.Since they couldn't rocket to Europa to see for themselves,they searched for similar forma- tions here on Earth.They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice.The scientists now suspect something similar might be happening on Europa:that as water and ice of different temperatures mingle and shift,the surface fractures.This would explain the jumbled ice sculptures."Fracturing catastrophically disrupts the ice in the same way that it causes ice shelves to collapse on Earth,"Schmidt told Science News.She and her team found that the process could be causing chaos terrains to form quickly on Europa.The new study suggests that on this moon,elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life.The size of Europa is a bit larger than that of Earth's moon.A:RightB:WrongC:Not mentioned

共用题干Europa's Watery UnderworldEuropa,one of Jupiter's 63 known moons,looks bright and icy on the surface.But appearances can be deceiving:Miles within its cracked,frigid shell,Europa probably hides giant pools of liquid water. Where scientists find liquid water,they hope to find life as well.Since we can't go diving into Europa's depths just yet,scientists instead have to investigate the moon's surface for clues to what lies beneath.In a new study,scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U.S.Great Lakes.Pictures of Europa,which is slightly smaller than Earth's moon,clearly show a tangled,icy mishmash of lines and cracks known as"chaos terrains".These chaotic places cover more than half of Europa. For more than 10 years,scientists have wondered what causes the formations.The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface.For scientists who suspect that Europa also may be hiding life beneath its icy surface,the news about the new lake is exciting."It would be great if these lakes harbored life,"Britney Schmidt,a planetary scientist who worked onthe study,told Science News."But even if they didn't,they say that Europa is doing something interesting and active right now."Schmidt,a scientist at the University of Texas at Austin,and her colleagues wanted to know how chaos terrains form.Since they couldn't rocket to Europa to see for themselves,they searched for similar forma- tions here on Earth.They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice.The scientists now suspect something similar might be happening on Europa:that as water and ice of different temperatures mingle and shift,the surface fractures.This would explain the jumbled ice sculptures."Fracturing catastrophically disrupts the ice in the same way that it causes ice shelves to collapse on Earth,"Schmidt told Science News.She and her team found that the process could be causing chaos terrains to form quickly on Europa.The new study suggests that on this moon,elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life.The strange ice patterns on Europa are formed as a result of a mixture of liquid water and solid material underground water pool.A:RightB:WrongC:Not mentioned

资料:A high-precision NASA radar instrument left a NASA airport in Southern California for Iceland on January 28 to create detailed maps of how glaciers move in the dead of winter. This will help scientists around the world better understand some of the most basic processes involved in melting glaciers, which are major contributors to rising sea levels.NASA used the same airborne instrument in June 2012 to map the summer flows of two Icelandic ice caps. The ice caps — large areas of permanent snow and ice cover — encompass multiple glaciers flowing in different directions and at different speeds. By mapping the same ice caps now, in winter, when the surface remains frozen all day, and then comparing the winter and summer velocities, the researchers will be able to isolate the effects of melt water.Above is a view of a small part of the Hofsjkull ice cap, which encompasses several glaciers. The fan at upper left is part of a glacier called Mlaj?kull.For more on the research, see this NASA press release.What does the underlined word permanent (paragragh 2) mean?A.Freeze easily.B.Move quickly.C.Long-lasting.D.Extremely cold.

资料:A high-precision NASA radar instrument left a NASA airport in Southern California for Iceland on January 28 to create detailed maps of how glaciers move in the dead of winter. This will help scientists around the world better understand some of the most basic processes involved in melting glaciers, which are major contributors to rising sea levels.NASA used the same airborne instrument in June 2012 to map the summer flows of two Icelandic ice caps. The ice caps — large areas of permanent snow and ice cover — encompass multiple glaciers flowing in different directions and at different speeds. By mapping the same ice caps now, in winter, when the surface remains frozen all day, and then comparing the winter and summer velocities, the researchers will be able to isolate the effects of melt water.Above is a view of a small part of the Hofsjkull ice cap, which encompasses several glaciers. The fan at upper left is part of a glacier called Mlaj?kull.For more on the research, see this NASA press release.How can the scientists figure out the effects of melting water?A.By melting the frozen iceberg in winter.B.By observing the snow's moving directions.C.By isolating ice from water in sunlines.D.By comparing the glaciers moving speeds.

共用题干New research from NASA scientists suggests emissions of black soot after the way sunlight re- flects off snow.According to a computer simulation,black soot may be responsible for 25 percent of observed global warming over the past century. Soot in the higher latitudes(维度)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.Soot 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 increase,as the soot becomes more con-centrated on the snow surface.“This provides a positive feedback,as glaciers and ice sheets melt, they tend to get even dirtier.”said Dr. James Hansen,a researcher at NASA's Goddard Institute for Space Studies,New York.Hansen found soot's effect on snow albedo(反照率),which may be contributing to trends to-ward early springs in the Northern Hemisphere,such as thinning Arctic sea ice and melting glac-iers permafrost. Soot also is believed to play a role in changes in the atmosphere above the oceans and land.“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 absorp-tion of solar energy is especially effective in warming the world's climate.“ This forcing is unusual-ly effective,causing twice as much global warming as a carbon-dioxide forcing of the same magni-tude.”Hansen noted.Hansen 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 the century.The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were coherent with the researchers' climate model situations,which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight. What is the main cause of climate warming during the past century?A: Soot.B: Snow.C: Greenhouse gases.D:.Wind.

共用题干New research from NASA scientists suggests emissions of black soot after the way sunlight re- flects off snow.According to a computer simulation,black soot may be responsible for 25 percent of observed global warming over the past century. Soot in the higher latitudes(维度)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.Soot 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 increase,as the soot becomes more con-centrated on the snow surface.“This provides a positive feedback,as glaciers and ice sheets melt, they tend to get even dirtier.”said Dr. James Hansen,a researcher at NASA's Goddard Institute for Space Studies,New York.Hansen found soot's effect on snow albedo(反照率),which may be contributing to trends to-ward early springs in the Northern Hemisphere,such as thinning Arctic sea ice and melting glac-iers permafrost. Soot also is believed to play a role in changes in the atmosphere above the oceans and land.“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 absorp-tion of solar energy is especially effective in warming the world's climate.“ This forcing is unusual-ly effective,causing twice as much global warming as a carbon-dioxide forcing of the same magni-tude.”Hansen noted.Hansen 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 the century.The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were coherent with the researchers' climate model situations,which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight.“This forcing” in Paragraph 5 refers to_____.A: sun's heating on snow surfaceB: soot's increased absorption of solar energyC: carbon-dioxide's warming effectD: snow's increased reflection of sunlight

共用题干Where Did the Earth's Water Come From?Earth is located within the"snow line"of the solar system,the region closest to the Sun where H2 0 is primarily in liquid or gaseous form,if at all.______(46)The snow line phenomena is reflected in the water content of planets like Mercury,Venus,and Mars. Water is absent on Mercury.On Venus,H2O only exists as a trace element in the atmosphere.Mars only has a thin veneer of ice in its polar regions.In general,water is rare within the snow line.Why does Earth have so much water relative to the other inner planets?71%of the surface is covered in the oceans,more than half of which is deeper than 3,000 meters,with an approximate total volume of 1.3 billion cu km.______(47)There are various theories as to where all the Earth's water came from,but several theories have fared better than the others.______(48)When the Earth was in the process of forming,with a radius just 40%smaller than at present,it would have had enough gravity to hold on to a tenuous atmosphere with water vapor. The first water vapor on the planet would have come from the planet's internals,where volatile(low weight)chemicals would have a tendency to float to the top,and heavy chemicals(iron and nickel)would sink.Though the first of Earth's water came about through volcanism,this alone probably didn't produce enough to form stable pools on the surface.______(49)Comparing the isotope ratios of water on Earth and water from comets and asteroids has revealed that the majority of the Earth's water comes from asteroids.Throughout its history,Earth's water has increased in volume due to biological processes. In the early seas of Earth,hydrogen sulfide would have been in great supply,which,when reacted with carbon dioxide from the atmosphere during photosynthesis in sulfide-reducing bacteria,would have produced hydrogen,sulfur,and water.______(50)________(49)A: More water was added to the planet during several hypothesized large impacts from asteroids from the outer asteroid belt.B:We know that the oceans existed as early as 100 million years after the formation of the Earth.C:Still,the oceans only make up 0.023%of the Earth's total mass.D:Astronomers say Earth s water may have come from space.E:The snow line is located in the outerasteroid belt,between the orbits of Mars and Jupiter. F: Many geologists believe that the majority of Earth's water generated through this process.

共用题干New research from NASA scientists suggests emissions of black soot after the way sunlight re- flects off snow.According to a computer simulation,black soot may be responsible for 25 percent of observed global warming over the past century. Soot in the higher latitudes(维度)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.Soot 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 increase,as the soot becomes more con-centrated on the snow surface.“This provides a positive feedback,as glaciers and ice sheets melt, they tend to get even dirtier.”said Dr. James Hansen,a researcher at NASA's Goddard Institute for Space Studies,New York.Hansen found soot's effect on snow albedo(反照率),which may be contributing to trends to-ward early springs in the Northern Hemisphere,such as thinning Arctic sea ice and melting glac-iers permafrost. Soot also is believed to play a role in changes in the atmosphere above the oceans and land.“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 absorp-tion of solar energy is especially effective in warming the world's climate.“ This forcing is unusual-ly effective,causing twice as much global warming as a carbon-dioxide forcing of the same magni-tude.”Hansen noted.Hansen 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 the century.The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were coherent with the researchers' climate model situations,which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight. The largest warming effects happened in the Northern Hemisphere with_____.A: thin sea ice and insufficient sunlightB: light、 snow cover and sufficient sunlightC: heavy snow cover and sufficient sunlightD:.thick sea ice and sufficient sunlight

共用题干New research from NASA scientists suggests emissions of black soot after the way sunlight re- flects off snow.According to a computer simulation,black soot may be responsible for 25 percent of observed global warming over the past century. Soot in the higher latitudes(维度)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.Soot 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 increase,as the soot becomes more con-centrated on the snow surface.“This provides a positive feedback,as glaciers and ice sheets melt, they tend to get even dirtier.”said Dr. James Hansen,a researcher at NASA's Goddard Institute for Space Studies,New York.Hansen found soot's effect on snow albedo(反照率),which may be contributing to trends to-ward early springs in the Northern Hemisphere,such as thinning Arctic sea ice and melting glac-iers permafrost. Soot also is believed to play a role in changes in the atmosphere above the oceans and land.“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 absorp-tion of solar energy is especially effective in warming the world's climate.“ This forcing is unusual-ly effective,causing twice as much global warming as a carbon-dioxide forcing of the same magni-tude.”Hansen noted.Hansen 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 the century.The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were coherent with the researchers' climate model situations,which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight. Which of the following statements of soot is NOT true?A: It absorbs sun's heat.B: It is responsible for climate change.C: It reflects sunlight.D:.It may account for a quarter of global warming over the past century.

共用题干New research from NASA scientists suggests emissions of black soot after the way sunlight re- flects off snow.According to a computer simulation,black soot may be responsible for 25 percent of observed global warming over the past century. Soot in the higher latitudes(维度)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.Soot 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 increase,as the soot becomes more con-centrated on the snow surface.“This provides a positive feedback,as glaciers and ice sheets melt, they tend to get even dirtier.”said Dr. James Hansen,a researcher at NASA's Goddard Institute for Space Studies,New York.Hansen found soot's effect on snow albedo(反照率),which may be contributing to trends to-ward early springs in the Northern Hemisphere,such as thinning Arctic sea ice and melting glac-iers permafrost. Soot also is believed to play a role in changes in the atmosphere above the oceans and land.“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 absorp-tion of solar energy is especially effective in warming the world's climate.“ This forcing is unusual-ly effective,causing twice as much global warming as a carbon-dioxide forcing of the same magni-tude.”Hansen noted.Hansen 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 the century.The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were coherent with the researchers' climate model situations,which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight. Which of the following areas shows a greater warming effect?A: Ice sea areas.B: Areas with black carbon.C: Areas covered with white snow.D: Melting glaciers.

单选题In regions where ice conditions prevail in the winter,().Athe lantern panes of unattended lights may not become covered with ice or snowBthe lantern panes of unattended lights may become covered with ice or snowCice or snow is likely caused coloredDthe white lights are likely caused to appear colored

单选题ATo examine the chemical elements in the Ice Age.BTo look into the pattern of solar wind activity.CTo analyze the composition of different trees.DTo find out the origin of carbon-14 on Earth.

单选题The scientists are not sure_______.Ahow long the ice age lastedBwhere ice sheets melted during the ice ageCwhat caused the temperature changesDwhat the earth is made up of

单选题According to the passage, the greatest part of the solar energy that reaches the Earth is _____.Areflected back to space by snow and iceBconcentrated at visible wavelengthsCabsorbed by carbon dioxide moleculesDabsorbed by atmospheric water vapor

单选题The wordstwo kinds in Line 4 mean the countries______.Awhich have snow either as yearly happening to celebrate or as rare weatherBwhich either have heavy snow or light snowCto which snow either causes problems or no problemsDwhich either have snow-ploughs or no snow-ploughs

单选题Others argue that since the earth has endured a long string of ice ages in the last two million to three million years, any warming is()to be temporary.AseemedBlikelyCtendedDpossible

单选题What is the best way to reduce the amount of soot?AInstalling exhaust filters on all trucks and buses.BBetter managing forest fires.CGetting Americans to give up SUVs.DMelting snow and ice.

单选题Between 65,000 and 35,000 years ago,______.Athe temperature changed a lotBthe earth was much warmer than it is nowCwinter isn't colder than summerDmost of the ice that melted was in the Northern hemisphere during the 30,000-year long ice age