Many Media Sources are reporting that global warming is affecting Antartica
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Some think the Warming Trend is nothing but hype...
Why would people think that???
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What is Clear is that we need to have more data!
The expert in the video above right (red jacket) calls for us to monitor the antarctic data more closely.
The Task page of this WebQuest will detail how we are going to gather and interpret Antarctic Ice and Temperature data to enable us to solidify our convictions about the changes that are happening in Antartica.
The Task page of this WebQuest will detail how we are going to gather and interpret Antarctic Ice and Temperature data to enable us to solidify our convictions about the changes that are happening in Antartica.
Summary
Support for the Global Warming Theory
Scientists who support the theory of global warming point to three kinds of evidence. The first is climate records. These records show rising surface temperatures in many places. The second is glacier records. They show that glaciers around the world are melting as temperatures rise. The third type of evidence is rising levels of greenhouse gases in the atmosphere. Studies of air bubbles trapped in polar ice show that greenhouse gas levels are the highest they've been in 420,000 years. Supporters of the global warming theory trace these changes back to the strut of the Industrial Revolution. During this time, many new machines were invented. Many were powered by the burning of fossil fuels. Today we use coal, oil, and natural gas to heat our homes, run our cars, and power our factories. As a result of this activity, we add more than 4 billion tons of carbon dioxide to the air every year. This gas will stay in our atmosphere for at least the next 100 years.
The results of global warming, these scientists warn, could have terrible consequences. Some biomes may lose plants and animals that are unable to adapt to warmer conditions. Crop failures may become common, leading to widespread hunger. Ocean levels may rise as polar ice melts. Higher seas may flood low-lying islands and coastal cities. The best way to prevent these disasters, these scientists say, is to reduce activities that create greenhouse gases. This could mean difficult changes in the way many people today live.
Doubts About the Global Warming Theory
Not all scientists agree with the global warming theory. Some doubt that Earth's temperature is, in fact, rising at all. Like supporters, the doubters support their views with evidence. They point out that temperature records of the upper atmosphere show little sign of warming. Most surface temperature records, they argue, come from urban areas. City buildings and pavement absorb more heat from the sun than green spaces. As a result, urban areas get warmer as they grow. What looks like global warming may just be city warming. The doubters also note that not all glaciers are shrinking. Some are growing. Some doubters accept evidence that Earth is warming. But they believe this is due to natural causes. Changes in the sun's energy or in ocean currents are far more likely to cause climate change, they believe, than human activity.
Finally, some doubters question whether rising temperatures will be so disastrous. People living in cold climates, they point out, might welcome warmer winters. Areas that are now too cold for crops might become productive farmland. Also, more carbon dioxide in the air may boost plant growth. The result could be faster growing crops and forests. This might be good, not bad, for many biomes.
Studying Temperatures in Antarctica
The impact of global warming on Antarctica could be dramatic. Warmer temperatures could cause glaciers and ice shelves to melt. If the area covered by ice shrinks, less energy from the sun would be reflected back into space. Temperatures would then rise even more.
To find out if such changes are likely, scientists gather data on air temperatures in many parts of Antarctica. They compare that data to records from recent years, noting any trends. Researchers also collect information about Antarctica's climate from thousands of years ago. The snow that falls here each year doesn't melt. Instead, it piles up in layers. The layers are thicker in wet years and thinner in dry ones.
Researchers drill deep into glaciers to take out cores of ice. An ice core looks like a very long pole with thin cross stripes. Each stripe, or layer, represents a year's snowfall. By examining the cores, researchers can learn what the climate was like when each layer of snow fell. They can determine how much precipitation fell and what temperatures were like for that year. The deeper they drill, the farther back in time they can look.http://www.pbs.org/wgbh/nova/warnings/stories/
Studying Ice Shelves in Antarctica
Ice shelves are floating sheets of ice that are still attached to the continent. Ice shelves form half of Antarctica's coastline and more than a tenth of its surface area. Every summer, the edges of Antarctic ice shelves break off to form icebergs. An iceberg is a large mass of ice floating around in the ocean. Researchers in Antarctica study ice shelves to see if they are growing or melting. They also watch for large chunks of ice that break off and float away. One way they do this is by placing cameras on satellites that orbit, or circle, Earth. The cameras take pictures of ice shelves as they form and break apart. Researchers also spend time at observation posts on or near ice shelves. From these posts they can study how seasonal temperature changes affect the ice shelves.
Studying Penguins in Antarctica
The Adelie is the most common penguin in this polar biome. Nearly 5 million Adelies call Antarctica home. Each summer they raise their young on the few areas of coastline that are not covered with ice. Global warming could be bad for Adelies. Warmer air can hold more moisture. This could lead to increased snowfall in Antarctica.
If snow covers the few bare spots that the penguins need for nesting, they might stop breeding. Researchers are studying how many Adelie penguins return to their nesting grounds each year. They do this by taking a simple census. This means counting the number of penguins at each nesting site. Researchers also try to track the birds' movements over the year. They glue transmitters on the penguins' feathers and use satellites to track the signals given off.
Beginning to Think Globally
In this chapter, you learned that Antarctica is a very cold, remote place. Researchers visit Antarctica to study global warming. They do this by gathering information on air temperatures, ice shelves, and penguins. Researchers don't always agree on what their studies show. For example, air temperatures are rising in some areas of Antarctica. This may be due to the greenhouse effect. But temperatures are falling in other areas. What this means is unclear. In recent years, researchers have seen huge chunks of ice shelves break off to form icebergs. But scientists aren't sure what is causing the breakups or what effects they will have on the polar biome. Researchers have also observed changes in penguin populations. There are far fewer Adelie penguins in some areas than in the past. But other penguin species are increasing their numbers. Neither change may be the result of global warming. Most scientists connect global warming to rising levels of greenhouse gases in the atmosphere. They argue that his rise comes from human activity, especially the burning of fossil fuels. But countries are very unequal in their use of fossil fuels.
Scientists who support the theory of global warming point to three kinds of evidence. The first is climate records. These records show rising surface temperatures in many places. The second is glacier records. They show that glaciers around the world are melting as temperatures rise. The third type of evidence is rising levels of greenhouse gases in the atmosphere. Studies of air bubbles trapped in polar ice show that greenhouse gas levels are the highest they've been in 420,000 years. Supporters of the global warming theory trace these changes back to the strut of the Industrial Revolution. During this time, many new machines were invented. Many were powered by the burning of fossil fuels. Today we use coal, oil, and natural gas to heat our homes, run our cars, and power our factories. As a result of this activity, we add more than 4 billion tons of carbon dioxide to the air every year. This gas will stay in our atmosphere for at least the next 100 years.
The results of global warming, these scientists warn, could have terrible consequences. Some biomes may lose plants and animals that are unable to adapt to warmer conditions. Crop failures may become common, leading to widespread hunger. Ocean levels may rise as polar ice melts. Higher seas may flood low-lying islands and coastal cities. The best way to prevent these disasters, these scientists say, is to reduce activities that create greenhouse gases. This could mean difficult changes in the way many people today live.
Doubts About the Global Warming Theory
Not all scientists agree with the global warming theory. Some doubt that Earth's temperature is, in fact, rising at all. Like supporters, the doubters support their views with evidence. They point out that temperature records of the upper atmosphere show little sign of warming. Most surface temperature records, they argue, come from urban areas. City buildings and pavement absorb more heat from the sun than green spaces. As a result, urban areas get warmer as they grow. What looks like global warming may just be city warming. The doubters also note that not all glaciers are shrinking. Some are growing. Some doubters accept evidence that Earth is warming. But they believe this is due to natural causes. Changes in the sun's energy or in ocean currents are far more likely to cause climate change, they believe, than human activity.
Finally, some doubters question whether rising temperatures will be so disastrous. People living in cold climates, they point out, might welcome warmer winters. Areas that are now too cold for crops might become productive farmland. Also, more carbon dioxide in the air may boost plant growth. The result could be faster growing crops and forests. This might be good, not bad, for many biomes.
Studying Temperatures in Antarctica
The impact of global warming on Antarctica could be dramatic. Warmer temperatures could cause glaciers and ice shelves to melt. If the area covered by ice shrinks, less energy from the sun would be reflected back into space. Temperatures would then rise even more.
To find out if such changes are likely, scientists gather data on air temperatures in many parts of Antarctica. They compare that data to records from recent years, noting any trends. Researchers also collect information about Antarctica's climate from thousands of years ago. The snow that falls here each year doesn't melt. Instead, it piles up in layers. The layers are thicker in wet years and thinner in dry ones.
Researchers drill deep into glaciers to take out cores of ice. An ice core looks like a very long pole with thin cross stripes. Each stripe, or layer, represents a year's snowfall. By examining the cores, researchers can learn what the climate was like when each layer of snow fell. They can determine how much precipitation fell and what temperatures were like for that year. The deeper they drill, the farther back in time they can look.http://www.pbs.org/wgbh/nova/warnings/stories/
Studying Ice Shelves in Antarctica
Ice shelves are floating sheets of ice that are still attached to the continent. Ice shelves form half of Antarctica's coastline and more than a tenth of its surface area. Every summer, the edges of Antarctic ice shelves break off to form icebergs. An iceberg is a large mass of ice floating around in the ocean. Researchers in Antarctica study ice shelves to see if they are growing or melting. They also watch for large chunks of ice that break off and float away. One way they do this is by placing cameras on satellites that orbit, or circle, Earth. The cameras take pictures of ice shelves as they form and break apart. Researchers also spend time at observation posts on or near ice shelves. From these posts they can study how seasonal temperature changes affect the ice shelves.
Studying Penguins in Antarctica
The Adelie is the most common penguin in this polar biome. Nearly 5 million Adelies call Antarctica home. Each summer they raise their young on the few areas of coastline that are not covered with ice. Global warming could be bad for Adelies. Warmer air can hold more moisture. This could lead to increased snowfall in Antarctica.
If snow covers the few bare spots that the penguins need for nesting, they might stop breeding. Researchers are studying how many Adelie penguins return to their nesting grounds each year. They do this by taking a simple census. This means counting the number of penguins at each nesting site. Researchers also try to track the birds' movements over the year. They glue transmitters on the penguins' feathers and use satellites to track the signals given off.
Beginning to Think Globally
In this chapter, you learned that Antarctica is a very cold, remote place. Researchers visit Antarctica to study global warming. They do this by gathering information on air temperatures, ice shelves, and penguins. Researchers don't always agree on what their studies show. For example, air temperatures are rising in some areas of Antarctica. This may be due to the greenhouse effect. But temperatures are falling in other areas. What this means is unclear. In recent years, researchers have seen huge chunks of ice shelves break off to form icebergs. But scientists aren't sure what is causing the breakups or what effects they will have on the polar biome. Researchers have also observed changes in penguin populations. There are far fewer Adelie penguins in some areas than in the past. But other penguin species are increasing their numbers. Neither change may be the result of global warming. Most scientists connect global warming to rising levels of greenhouse gases in the atmosphere. They argue that his rise comes from human activity, especially the burning of fossil fuels. But countries are very unequal in their use of fossil fuels.