In this task, you are given news articles and you need to generate a highlight, i.e., a short summary, with a maximum length of 10 lines.

(CNN) -- Explorer Dennis Schmitt found an island nearly two years ago near Greenland. Fishermen pass by Greenland's Ilulissat fjord in this September 2004 picture. Such a discovery would usually elicit curiosity, even wonder perhaps, but it evoked mixed feelings for the explorer. The island was once thought to be a peninsula attached to Greenland by an ice shelf or a glacier. But such a large amount of ice melted, it revealed the distinct island. "I very quickly realized two things," he told CNN's Anderson Cooper during a visit to the island earlier this year. "One [was] that this was going to be significant because it was going to be an example of climate change." "The other thing was that it meant it was really happening. It wasn't a joke. It wasn't just statistics. It was really happening." He calls his discovery Warming Island. Many climatologists and scientists say arctic ice melt and other changes in the Earth's climate are the result of an increase in the world's temperature, a trend widely called global warming. Many global warming experts say the phenomenon, if unchecked, is capable of altering the world's climate and geography. In the worst-case scenario, experts say oceans could rise to overwhelming and catastrophic levels, flooding cities and altering seashores. Other scientists and observers, a minority compared to those who believe the warming trend is something ominous, say it is simply the latest shift in the cyclical patterns of a planet's life. Most of the scientific community believes that some warming is occurring across the globe and through some layers of the atmosphere. But why it is occurring and what that means for the future is scientifically and politically contentious. The Earth's temperature averages about 60 degrees Fahrenheit (about 16 degrees Celsius). The average surface temperature has warmed one degree Fahrenheit (0.6 degrees Celsius) during the last century, according to the National Research Council. The temperatures were relatively unchanged from 1880 to 1910, according to the U.S. Environmental Protection Agency. They rose till about 1945, cooled until about 1975 and have risen steadily to present day. There are several possible reasons for the warming, scientists say. A change in the Earth's orbit or the intensity of the sun's radiation could change, triggering warming or cooling. The reason most cited -- by scientists and scientific organizations -- for the current warming trend is an increase in the concentrations of greenhouse gases, which are in the atmosphere naturally and help keep the planet's temperature at a comfortable level. The amount of carbon dioxide in the atmosphere, for instance, has increased by 35 percent since the dawn of the industrial age, according to the United Nations' Intergovernmental Panel on Climate Change, commonly referred to as the IPCC. The presence of methane is now 151 percent above pre-industrial levels, but the rate of increase has slowed in recent decades, according to the EPA. Meanwhile, nitrous oxide increased by about 18 percent during the past 200 years. Many scientists and experts who have studied global warming believe the increase is primarily the result of human activities, like the burning of fossil fuels, emissions from vehicles and the clearing of forests. "For the last 30 years, there's no way there's anything natural that can explain it," Stephen Schneider, a professor of environmental studies at Stanford University in California, said. "A vast bulk of the knowledgeable and honest community ... will say the science is settled and humans are at least a majority of the reason behind the warming," he added. Many scientific organizations share Schneider's view, ranging from the national academies of the countries that comprise the G8 to the National Research Council, the American Meteorological Society and the American Geophysical Union. But there are those who do not share his view, and among the skeptics is Richard Lindzen, a professor of atmospheric sciences at the Massachusetts Institute of Technology. "We've suddenly taken to reading tea leaves," he said. "When we saw cooling from 1940 to 1970, we were proclaiming global cooling. Since then, there's been a few tenths of global warming, so we're proclaiming global warming." He believes the current warming trend is the result of natural variability, where a planet goes through phases of warming and cooling and the human contribution to it is minimal. "The Earth is always getting colder and warmer," he said. "It's always changing. In fact, this is true of any fluid-covered planet." Asked about glacial melt, which many observers point to as evidence of global warming, Lindzen said the way glaciers change and move are phenomena largely unexplained. "We don't know why, but it's perfectly clear that glaciers change even though the temperature is cooling at the place that they've occurred," he said. "What we're doing is cherry picking any event that occurs and then saying that's occurring due to global warming." Yet, for Schneider, it is a cause for concern and alarm. "We're already in serious melt, nobody can explain it. The models don't predict it," he said. "We don't know what's going on up there. All we know is that we could be triggering something really nasty." The greatest point of contention is the possible implications for future political and economic policies for the world's nations. The IPCC in February 2007 projected that if carbon dioxide levels doubled relative to pre-industrial levels, temperatures could rise between 3.6 to 8.1 degrees Fahrenheit (2 to 4.5 degrees Celsius) by 2100. The lower end of the range could cause more intense hurricanes, droughts, wildfires and flooding, Schneider said. The higher end could lead to the catastrophes commonly associated with the visions of Hollywood filmmakers. Uncertainties, however, plague such forecasts, which are based on computer simulations and models. The models contemplate factors associated with how the atmosphere, oceans and continents interact, all natural elements that have unpredictability intrinsic to them. "Exactly how much it's going to warm up, we don't know," Schneider said. "That it's going to warm up? I'd bet anything on that." E-mail to a friend .
Earth has warmed one degree in past 100 years .
Majority of scientists say greenhouse gases are causing temperatures to rise .
Some critics say planets often in periods of warming or cooling .

(CNN) -- Poetry, performance and prayer celebrated the voice of literary giant Maya Angelou at a memorial service held Saturday at Wake Forest University in Winston-Salem, North Carolina. "She taught us that we are each wonderfully made, intricately woven and put on this earth for a purpose," first lady Michelle Obama said during her tribute to the celebrated poet and actress. Angelou, 86, died at her Winston-Salem home on May 28. Angelou had been "frail" and suffering from heart problems, her literary agent said. Angelou taught American studies for years at Wake Forest. Obama did not meet Angelou until 2008, while on the campaign trail, but she said Angelou's poem 'Phenomenal Woman' had a profound impact on her life. "I was struck by how she celebrated black women's beauty like no one had ever dared to," Obama said in the service held at Wait Chapel. "She also graced us with an anthem for all women, a call to all of us to embrace our God-given beauty. How desperately black girls needed that message," the first lady said, remembering that as a young girl her first doll was a white Malibu Barbie. She said that Angelou reminded everyone that " We must each find our own voice, decide our own value and then announce it to the world with all the pride and joy that is our birthright as members of the human race." 'Spiritual queen mother' Oprah Winfrey remembered her friend as the greatest woman she has ever known. "The loss I feel I cannot describe," Winfrey said, holding back tears. "It's like something I've never felt before. She was my spiritual queen mother and everything that that word implies. She taught me the poetry of courage and respect." Winfrey recalled meeting Angelou in the late 1970s, when she worked as a news reporter. "She looked at me and said, 'Who are you girl?'" Winfrey said. "I will miss her." 'She had the voice of God' "I Loved Maya," said former President Bill Clinton during his reflection. He said the two last met in April in Austin during a celebration of of the 50th anniversary of the Civil Rights Act. Clinton recalled that he hugged Angelou and said, " I cannot believe that you have gotten yourself here." He said she responded, "Just because I'm wheelchair-bound doesn't mean I don't get around." Clinton became aware of Angelou while in college by reading her book. "I Know Why the Caged Bird Sings," her lasting contribution to literature that bore witness to the brutality of a Jim Crow South. He said Angelou was always paying attention and used her voice to call attention to the things that really mattered. "God loaned her his voice. She had the voice of God and he decided he wanted it back from her," Clinton told the audience. Music and more . Actress Cicely Tyson reflected on a friendship that began in 1960, when both were in a play called "The Blacks," which ran for three years. "Every emotion known to man was exhibited by Maya. She held nothing (back). She spoke her mind no matter what the situation," Tyson remembered. The memorial service also featured singer Lee Ann Womack performing "I Hope You Dance," considered Angelou's favorite song. At the conclusion of the service Saturday, Angelou's voice once more was heard in a recording of the 1996 Ashford & Simpson song "Been Found." Maya Angelou remembered by those she inspired . Legendary author Maya Angelou dies at age 86 .
Memorial service celebrates life and work of Maya Angelou .
Michelle Obama: "She celebrated black women's beauty like no one had ever dared to"
Oprah Winfrey: "The loss I feel I cannot describe"
Bill Clinton: "God loaned her his voice"

(CNN) -- A fire erupted Friday at the headquarters of the Shanksville, Pennsylvania, memorial to United Airlines Flight 93, which crashed on September 11, 2001, officials said. "There is a potential for 9/11 memorabilia loss due to a fire," according to a statement from the National Park Service, but the extent of the damage is not known yet. NPS spokesman Mike Litterst said 10% of the archives and museum collection was stored in the damaged buildings, but much of it was kept in a fireproof safe. Among the items in the damaged buildings was a U.S. flag that flew over the U.S. Capitol on the day of the terrorist attack. The flag was given to the Flight 93 National Memorial last September 11. Its status was not known. Four buildings were damaged, the park service said. Heavy rain helped the firefighting efforts. Seven fire companies responded to the blaze, which started about 3 p.m., said Geraldine Budzina, a Somerset County dispatcher. No injuries were reported. "I think stuff has been lost" Ken Nacke, whose brother Louis was on Flight 93, said many 9/11 artifacts -- including notes and other mementos left at a temporary memorial at the crash site -- were being stored in the area where the fire burned. He said he had spoken Friday with the head of Families of Flight 93 shortly after the group president was contacted by the memorial's superintendent. "I think stuff has been lost," Nacke said. "I just don't know what has been lost. I know the layout of the buildings and I wouldn't be surprised. It's heartbreaking that we spent all this time to have this happen. All the blood sweat and tears that went into building this." Nacke helped raise funds for the Flight 93 National Memorial and advised in its planning. "At the temporary memorial, people would leave cards, T-shirts and handmade stuff that was very comforting to us," he said. "That's why it's heartbreaking. I hope none of this stuff is lost." Cause of fire is unknown . Clouds of dark smoke could be seen billowing into the blue sky over the grounds Friday afternoon on a live webcam. "We are deeply saddened to learn that a fire occurred at the Flight 93 National Memorial headquarters," Gordon Felt, president of Families of Flight 93 said in a statement. "We understand that no one was injured, and we are grateful for that." "Neither the memorial proper nor the new visitor center currently under construction were affected, as the headquarters is located approximately two miles from those sites," Litterst said. Initial reports were of extensive damage to the complex, Litterst said. All employees and volunteers were safely evacuated. The cause of the blaze is under investigation, he said. 40 people died in the plane crash . The memorial park is dedicated to the 40 passengers and crew who died when Flight 93 crashed outside the town in southwestern Pennsylvania. The plane went down, killing all on board, as passengers fought back against the hijackers, according to investigations. The memorial, still incomplete, includes a visitor center with traditional and interactive exhibits, public programs and information about the history of Flight 93. United Airlines Flight 93 was traveling from Newark, New Jersey, to San Francisco when hijackers took over the plane, according to the 9/11 Commission. Investigators said the terrorists were most likely trying to turn the airplane toward Washington to hit a major political target. The 2,200-acre memorial park is managed by the National Park Service. The second phase of construction is to be completed by 2015. Since 2001, more than 1 million people from around the world have visited the crash site. What you need to know about the Flight 93 National Memorial . CNN's Aaron Cooper, Deanna Hackney and Laura Bernardini contributed to this report.

NEW: Some 911 artifacts may have been damaged, park service says .
Fire breaks out at headquarters of memorial to United Airlines Flight 93 .
Headquarters complex is about two miles from the memorial in Pa.
Flight 93 crashed on September 11, 2001, after hijackers took over the plane .

