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    Facebook, Google and Twitter to testify in Congress over extremist content.

     

    Firms to give evidence in Senate on combating spread of extremist propaganda, while Twitter misses Russian election interference information deadline.

    ‘I’m disappointed in Twitter,’ said Senator Mark Warner after the company failed to send the required information to the Senate intelligence committee. Photograph: Danita Delimont/Getty Images/Gallo Images.

    Twitter, Facebook and Google are to be hauled in front of the US Congress again, to give testimony to the Senate Committee on Commerce, Science and Transportation for extremist content.

    On 17 January, the three companies are required to give evidence on the steps they are taking to combat the spread of extremist propaganda over the internet, the committee has announced, in a hearing titled “Terrorism and Social Media: Is Big Tech Doing Enough?”.

    As with the last major congressional enquiry, into Russian interference in US elections, none of the firms are sending their most senior executives. Instead, the heads of public policy at Twitter, Facebook and YouTube will be speaking for their companies.

    The hearing will come a week after the deadline given to the three companies to share information with the Senate intelligence committee about Russian interference. Facebook, Google and Twitter were supposed to respond to a series of detailed written questions from the committee, and while the former two did, Twitter’s reply is still nowhere to be found, two days after the deadline.

    “Facebook and Google met the deadline, and [with] voluminous amounts of information, Twitter did not,” Senator Mark Warner, the ranking Democrat on the Committee, told new media site Axios. “I’m disappointed in Twitter.”

    “They need to understand when they bring in their senior executives and testify before Congress, when Congress then has follow-up written questions, we expect them to answer those questions,” Warner added. “So if it’s a day or two, fine, but if this is one more attempt for them to kind of punt on their responsibility that will not go down well with the committee.”

     

    Twitter said it “looked forward to finalizing” its responses to the intelligence committee soon.

    “We are continuing to work closely with committee investigators to provide detailed, thorough answers to their questions,” it said in a statement. “As our review is ongoing, we want to ensure we are providing Congress with the most complete, accurate answers possible.”

    Both Twitter and Facebook face an equally strict deadline on the other side of the Atlantic. Damian Collins MP, chair of the DCMS select committee, has given the social networks until 18 January to hand over detailed information about Russian involvement in British votes, including the EU referendum, which they failed to provide when asked in December.

    https://www.theguardian.com/technology/2018/jan/10/facebook-google-twitter-testify-congress-extremist-content-russian-election-interference-information?utm_source=esp&utm_medium=Email&utm_campaign=GU+Today+main+NEW+H+categories&utm_term=260061&subid=19413045&CMP=EMCNEWEML6619I2 

     


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    What Is Global Warming? The planet is heating up—and fast.

     

    A polar bear stands sentinel on Rudolf Island in Russia’s Franz Josef Land archipelago, where the perennial ice is melting. Photograph by Cory Richards.

    Glaciers are melting, sea levels are rising, cloud forests are dying, and wildlife is scrambling to keep pace. It's becoming clear that humans have caused most of the past century's warming by releasing heat-trapping gases as we power our modern lives. Called greenhouse gases, their levels are higher now than in the last 650,000 years.

    We call the result global warming, but it is causing a set of changes to the Earth's climate, or long-term weather patterns, that varies from place to place. As the Earth spins each day, the new heat swirls with it, picking up moisture over the oceans, rising here, settling there. It's changing the rhythms of climate that all living things have come to rely upon.

    What will we do to slow this warming? How will we cope with the changes we've already set into motion? While we struggle to figure it all out, the face of the Earth as we know it—coasts, forests, farms and snow-capped mountains—hangs in the balance.

    Greenhouse effect.

    The "greenhouse effect" is the warming that happens when certain gases in Earth's atmosphere trap heat. These gases let in light but keep heat from escaping, like the glass walls of a greenhouse.

    First, sunlight shines onto the Earth's surface, where it is absorbed and then radiates back into the atmosphere as heat. In the atmosphere, “greenhouse” gases trap some of this heat, and the rest escapes into space. The more greenhouse gases are in the atmosphere, the more heat gets trapped.

    Scientists have known about the greenhouse effect since 1824, when Joseph Fourier calculated that the Earth would be much colder if it had no atmosphere. This greenhouse effect is what keeps the Earth's climate livable. Without it, the Earth's surface would be an average of about 60 degrees Fahrenheit cooler.

    In 1895, the Swedish chemist Svante Arrhenius discovered that humans could enhance the greenhouse effect by making carbon dioxide, a greenhouse gas. He kicked off 100 years of climate research that has given us a sophisticated understanding of global warming.

    Levels of greenhouse gases (GHGs) have gone up and down over the Earth's history, but they have been fairly constant for the past few thousand years. Global average temperatures have stayed fairly constant over that time as well, until recently. Through the burning of fossil fuels and other GHG emissions, humans are enhancing the greenhouse effect and warming Earth.

    Scientists often use the term "climate change" instead of global warming. This is because as the Earth's average temperature climbs, winds and ocean currents move heat around the globe in ways that can cool some areas, warm others, and change the amount of rain and snow falling. As a result, the climate changes differently in different areas.

    Aren't temperature changes natural?

    The average global temperature and concentrations of carbon dioxide (one of the major greenhouse gases) have fluctuated on a cycle of hundreds of thousands of years as the Earth's position relative to the sun has varied. As a result, ice ages have come and gone.

    However, for thousands of years now, emissions of GHGs to the atmosphere have been balanced out by GHGs that are naturally absorbed. As a result, GHG concentrations and temperature have been fairly stable. This stability has allowed human civilization to develop within a consistent climate.

    Occasionally, other factors briefly influence global temperatures. Volcanic eruptions, for example, emit particles that temporarily cool the Earth's surface. But these have no lasting effect beyond a few years. Other cycles, such as El Niño, also work on fairly short and predictable cycles.

    Now, humans have increased the amount of carbon dioxide in the atmosphere by more than a third since the industrial revolution. Changes this large have historically taken thousands of years, but are now happening over the course of decades.

    Why is this a concern?

    The rapid rise in greenhouse gases is a problem because it is changing the climate faster than some living things may be able to adapt. Also, a new and more unpredictable climate poses unique challenges to all life.

    Historically, Earth's climate has regularly shifted back and forth between temperatures like those we see today and temperatures cold enough that large sheets of ice covered much of North America and Europe. The difference between average global temperatures today and during those ice ages is only about 5 degrees Celsius (9 degrees Fahrenheit), and these swings happen slowly, over hundreds of thousands of years.

    Now, with concentrations of greenhouse gases rising, Earth's remaining ice sheets (such as Greenland and Antarctica) are starting to melt too. The extra water could potentially raise sea levels significantly.

    As the mercury rises, the climate can change in unexpected ways. In addition to sea levels rising, weather can become more extreme. This means more intense major storms, more rain followed by longer and drier droughts (a challenge for growing crops), changes in the ranges in which plants and animals can live, and loss of water supplies that have historically come from glaciers.

    https://www.nationalgeographic.com/environment/global-warming/global-warming-overview/

     


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