Questões de Vestibular Comentadas sobre inglês

When will the Amazon hit a tipping point?

    Scientists say climate change, deforestation and fires could cause the world’s largest rainforest to dry out. The big question is how soon that might happen. Seen from a monitoring tower above the treetops near Manaus, in the Brazilian Amazon, the rainforest canopy stretches to the horizon as an endless sea of green. It looks like a rich and healthy ecosystem, but appearances are deceiving. This rainforest — which holds 16,000 separate tree species — is slowly drying out.

    Over the past century, the average temperature in the forest has risen by 1-1.5 ºC. In some parts, the dry season has expanded during the past 50 years, from four months to almost five. Severe droughts have hit three times since 2005. That’s all driving a shift in vegetation. In 2018, a study reported that trees that do best in moist conditions, such as tropical legumes from the genus Inga, are dying. Those adapted to drier climes, such as the Brazil nut tree (Bertholletia excelsa), are thriving.

    At the same time, large parts of the Amazon, the world’s largest rainforest, are being cut down and burnt. Tree clearing has already shrunk the forest by around 15% from its 1970s extent of more than 6 million square kilometres; in Brazil, which contains more than half the forest, more than 19% has disappeared. Last year, deforestation in Brazil spiked by around 30% to almost 10,000 km2 , the largest loss in a decade. And in August 2019, videos of wildfires in the Amazon made international headlines. The number of fires that month was the highest for any August since an extreme drought in 2010.

(www.nature.com, 25.02.2020. Adaptado.)

When will the Amazon hit a tipping point?

    Scientists say climate change, deforestation and fires could cause the world’s largest rainforest to dry out. The big question is how soon that might happen. Seen from a monitoring tower above the treetops near Manaus, in the Brazilian Amazon, the rainforest canopy stretches to the horizon as an endless sea of green. It looks like a rich and healthy ecosystem, but appearances are deceiving. This rainforest — which holds 16,000 separate tree species — is slowly drying out.

    Over the past century, the average temperature in the forest has risen by 1-1.5 ºC. In some parts, the dry season has expanded during the past 50 years, from four months to almost five. Severe droughts have hit three times since 2005. That’s all driving a shift in vegetation. In 2018, a study reported that trees that do best in moist conditions, such as tropical legumes from the genus Inga, are dying. Those adapted to drier climes, such as the Brazil nut tree (Bertholletia excelsa), are thriving.

    At the same time, large parts of the Amazon, the world’s largest rainforest, are being cut down and burnt. Tree clearing has already shrunk the forest by around 15% from its 1970s extent of more than 6 million square kilometres; in Brazil, which contains more than half the forest, more than 19% has disappeared. Last year, deforestation in Brazil spiked by around 30% to almost 10,000 km2 , the largest loss in a decade. And in August 2019, videos of wildfires in the Amazon made international headlines. The number of fires that month was the highest for any August since an extreme drought in 2010.

(www.nature.com, 25.02.2020. Adaptado.)

When will the Amazon hit a tipping point?

    Scientists say climate change, deforestation and fires could cause the world’s largest rainforest to dry out. The big question is how soon that might happen. Seen from a monitoring tower above the treetops near Manaus, in the Brazilian Amazon, the rainforest canopy stretches to the horizon as an endless sea of green. It looks like a rich and healthy ecosystem, but appearances are deceiving. This rainforest — which holds 16,000 separate tree species — is slowly drying out.

    Over the past century, the average temperature in the forest has risen by 1-1.5 ºC. In some parts, the dry season has expanded during the past 50 years, from four months to almost five. Severe droughts have hit three times since 2005. That’s all driving a shift in vegetation. In 2018, a study reported that trees that do best in moist conditions, such as tropical legumes from the genus Inga, are dying. Those adapted to drier climes, such as the Brazil nut tree (Bertholletia excelsa), are thriving.

    At the same time, large parts of the Amazon, the world’s largest rainforest, are being cut down and burnt. Tree clearing has already shrunk the forest by around 15% from its 1970s extent of more than 6 million square kilometres; in Brazil, which contains more than half the forest, more than 19% has disappeared. Last year, deforestation in Brazil spiked by around 30% to almost 10,000 km2 , the largest loss in a decade. And in August 2019, videos of wildfires in the Amazon made international headlines. The number of fires that month was the highest for any August since an extreme drought in 2010.

(www.nature.com, 25.02.2020. Adaptado.)

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America’s social-media addiction is getting worse

(Sources: Pew Research Centre; e Marketer)

   A survey in January and February 2019 from the Pew Research Centre, a think tank, found that 69% of American adults use Facebook; of these users, more than half visit the site “several times a day”. YouTube is even more popular, with 73% of adults saying they watch videos on the platform. For those aged 18 to 24, the figure is 90%. Instagram, a photo-sharing app, is used by 37% of adults. When Pew first conducted the survey in 2012, only a slim majority of Americans used Facebook. Fewer than one in ten had an Instagram account.

    Americans are also spending more time than ever on social-media sites like Facebook. There is evidence that limiting such services might yield health benefits. A paper published last year by Melissa Hunt, Rachel Marx, Courtney Lipson and Jordyn Young, all of the University of Pennsylvania, found that limiting social-media usage to 10 minutes a day led to reductions in loneliness, depression, anxiety and fear. Another paper from 2014 identified a link between heavy social-media usage and depression, largely due to a “social comparison” phenomenon, whereby users compare themselves to others and come away with lower evaluations of themselves. 

(www.economist.com, 08.08.2019. Adaptado.)

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America’s social-media addiction is getting worse

(Sources: Pew Research Centre; e Marketer)

   A survey in January and February 2019 from the Pew Research Centre, a think tank, found that 69% of American adults use Facebook; of these users, more than half visit the site “several times a day”. YouTube is even more popular, with 73% of adults saying they watch videos on the platform. For those aged 18 to 24, the figure is 90%. Instagram, a photo-sharing app, is used by 37% of adults. When Pew first conducted the survey in 2012, only a slim majority of Americans used Facebook. Fewer than one in ten had an Instagram account.

    Americans are also spending more time than ever on social-media sites like Facebook. There is evidence that limiting such services might yield health benefits. A paper published last year by Melissa Hunt, Rachel Marx, Courtney Lipson and Jordyn Young, all of the University of Pennsylvania, found that limiting social-media usage to 10 minutes a day led to reductions in loneliness, depression, anxiety and fear. Another paper from 2014 identified a link between heavy social-media usage and depression, largely due to a “social comparison” phenomenon, whereby users compare themselves to others and come away with lower evaluations of themselves. 

(www.economist.com, 08.08.2019. Adaptado.)

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America’s social-media addiction is getting worse

(Sources: Pew Research Centre; e Marketer)

   A survey in January and February 2019 from the Pew Research Centre, a think tank, found that 69% of American adults use Facebook; of these users, more than half visit the site “several times a day”. YouTube is even more popular, with 73% of adults saying they watch videos on the platform. For those aged 18 to 24, the figure is 90%. Instagram, a photo-sharing app, is used by 37% of adults. When Pew first conducted the survey in 2012, only a slim majority of Americans used Facebook. Fewer than one in ten had an Instagram account.

    Americans are also spending more time than ever on social-media sites like Facebook. There is evidence that limiting such services might yield health benefits. A paper published last year by Melissa Hunt, Rachel Marx, Courtney Lipson and Jordyn Young, all of the University of Pennsylvania, found that limiting social-media usage to 10 minutes a day led to reductions in loneliness, depression, anxiety and fear. Another paper from 2014 identified a link between heavy social-media usage and depression, largely due to a “social comparison” phenomenon, whereby users compare themselves to others and come away with lower evaluations of themselves. 

(www.economist.com, 08.08.2019. Adaptado.)

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America’s social-media addiction is getting worse

(Sources: Pew Research Centre; e Marketer)

   A survey in January and February 2019 from the Pew Research Centre, a think tank, found that 69% of American adults use Facebook; of these users, more than half visit the site “several times a day”. YouTube is even more popular, with 73% of adults saying they watch videos on the platform. For those aged 18 to 24, the figure is 90%. Instagram, a photo-sharing app, is used by 37% of adults. When Pew first conducted the survey in 2012, only a slim majority of Americans used Facebook. Fewer than one in ten had an Instagram account.

    Americans are also spending more time than ever on social-media sites like Facebook. There is evidence that limiting such services might yield health benefits. A paper published last year by Melissa Hunt, Rachel Marx, Courtney Lipson and Jordyn Young, all of the University of Pennsylvania, found that limiting social-media usage to 10 minutes a day led to reductions in loneliness, depression, anxiety and fear. Another paper from 2014 identified a link between heavy social-media usage and depression, largely due to a “social comparison” phenomenon, whereby users compare themselves to others and come away with lower evaluations of themselves. 

(www.economist.com, 08.08.2019. Adaptado.)

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America’s social-media addiction is getting worse

(Sources: Pew Research Centre; e Marketer)

   A survey in January and February 2019 from the Pew Research Centre, a think tank, found that 69% of American adults use Facebook; of these users, more than half visit the site “several times a day”. YouTube is even more popular, with 73% of adults saying they watch videos on the platform. For those aged 18 to 24, the figure is 90%. Instagram, a photo-sharing app, is used by 37% of adults. When Pew first conducted the survey in 2012, only a slim majority of Americans used Facebook. Fewer than one in ten had an Instagram account.

    Americans are also spending more time than ever on social-media sites like Facebook. There is evidence that limiting such services might yield health benefits. A paper published last year by Melissa Hunt, Rachel Marx, Courtney Lipson and Jordyn Young, all of the University of Pennsylvania, found that limiting social-media usage to 10 minutes a day led to reductions in loneliness, depression, anxiety and fear. Another paper from 2014 identified a link between heavy social-media usage and depression, largely due to a “social comparison” phenomenon, whereby users compare themselves to others and come away with lower evaluations of themselves. 

(www.economist.com, 08.08.2019. Adaptado.)

Leia o texto para responder à questão.

America’s social-media addiction is getting worse

(Sources: Pew Research Centre; e Marketer)

   A survey in January and February 2019 from the Pew Research Centre, a think tank, found that 69% of American adults use Facebook; of these users, more than half visit the site “several times a day”. YouTube is even more popular, with 73% of adults saying they watch videos on the platform. For those aged 18 to 24, the figure is 90%. Instagram, a photo-sharing app, is used by 37% of adults. When Pew first conducted the survey in 2012, only a slim majority of Americans used Facebook. Fewer than one in ten had an Instagram account.

    Americans are also spending more time than ever on social-media sites like Facebook. There is evidence that limiting such services might yield health benefits. A paper published last year by Melissa Hunt, Rachel Marx, Courtney Lipson and Jordyn Young, all of the University of Pennsylvania, found that limiting social-media usage to 10 minutes a day led to reductions in loneliness, depression, anxiety and fear. Another paper from 2014 identified a link between heavy social-media usage and depression, largely due to a “social comparison” phenomenon, whereby users compare themselves to others and come away with lower evaluations of themselves. 

(www.economist.com, 08.08.2019. Adaptado.)

Leia o texto para responder à questão.

America’s social-media addiction is getting worse

(Sources: Pew Research Centre; e Marketer)

   A survey in January and February 2019 from the Pew Research Centre, a think tank, found that 69% of American adults use Facebook; of these users, more than half visit the site “several times a day”. YouTube is even more popular, with 73% of adults saying they watch videos on the platform. For those aged 18 to 24, the figure is 90%. Instagram, a photo-sharing app, is used by 37% of adults. When Pew first conducted the survey in 2012, only a slim majority of Americans used Facebook. Fewer than one in ten had an Instagram account.

    Americans are also spending more time than ever on social-media sites like Facebook. There is evidence that limiting such services might yield health benefits. A paper published last year by Melissa Hunt, Rachel Marx, Courtney Lipson and Jordyn Young, all of the University of Pennsylvania, found that limiting social-media usage to 10 minutes a day led to reductions in loneliness, depression, anxiety and fear. Another paper from 2014 identified a link between heavy social-media usage and depression, largely due to a “social comparison” phenomenon, whereby users compare themselves to others and come away with lower evaluations of themselves. 

(www.economist.com, 08.08.2019. Adaptado.)