So began the Monks Wood Wilderness experiment, which is now 60 years old. A rewilding study before the term existed, it shows how allowing land to naturally regenerate can expand native woodland and help tackle climate change and biodiversity loss. How new woodland generates itself. A shrubland of thorn thickets emerged after the first 10 to 15 The scientific method is the gold standard for exploring our natural world, and scientists use it to better understand climate change. (a statement that an experiment can test) Make observations (conduct experiments and gather data) In one OMG study, scientists discovered that many Greenland glaciers extend deeper (some around 1,000 Words in This Story. chemical - adj. of or relating to chemistry. chemicals - n. elements found in nature or made by people; substances used in the science of chemistry. imperfection - n. a Some time ago, scientists began experiments to find out (31) ______ it would be possible to set up a "village" under the sea. A special room was built and lowered (32) ______ the water of Port Sudan in the Red Sea. For 29 days, five men lived at a depth of 40 feet. At a (33) ______ lower level, another two divers stayed for a week in a smaller Bernard established animal experimentation as part of the standard scientific method. Drug testing using animals became important in the twentieth century. In 1937, a pharmaceutical company in the USA created a preparation of sulfanilamide, using diethylene glycol (DEG) as a solvent, and called the preparation 'Elixir Sulfanilamide'. cash. Some time ago, scientists began experiments to find out …………. it would be possible to set up a "village" under the sea. A special room was built and lowered into the water of Port Sudan in the Red Sea. For 29 days, five men lived at a depth of 40 feet. At a .......2….... lower level, another two divers stayed for a week in a smaller "house". On returning to the surface, the men said that they had experienced no difficulty in breathing and had made many interesting scientific observations. The captain of the party, Commander Cousteau, spoke of the possibility of cultivating the seabed. He said that some permanent stations were to be ….……. under the sea, and some undersea farms would provide food for the growing population of the nhật ngày 28-11-2022Chia sẻ bởi Ly a longSome time ago, scientists began experiments to find out …………. it would be possible to set up a "village" under the sea. A special room was built and lowered into the water of Port Sudan in the Red Sea. For 29 days, five men lived at a depth of 40 feet. At a .......2….... lower level, another two divers stayed for a week in a smaller "house". On returning to the surface, the men said that they had experienced no difficulty in breathing and had made many interesting scientific observations. The captain of the party, Commander Cousteau, spoke of the possibility of cultivating the seabed. He said that some permanent stations were to be ….……. under the sea, and some undersea farms would provide food for the growing population of the đề liên quanSome time ago, scientists began experiments to find out …………. it would be possible to set up a "village" under the sea. A special room was built and lowered into the water of Port Sudan in the Red Sea. For 29 days, five men lived at a depth of 40 feet. At a ........... lower level, another two divers stayed for a week in a smaller "house". On returning to the surface, the men said that they had experienced no difficulty in breathing and had made many interesting scientific observations. The captain of the party, Commander Cousteau, spoke of the possibility of cultivating the seabed. He said that some permanent stations were to be ….…3…. under the sea, and some undersea farms would provide food for the growing population of the life in the countryside which is often considered to be simple and traditional, life in the city is modern and complicated. People, from different regions, move to the cities in the hope of having a better life for them and their children. The inhabitants in city work as secretaries, businessmen, teachers, government workers, factory workers and even street vendors or construction workers. The high cost of living requires city dwellers, especially someone with low income, to work harder or to take a part-time job. For many people, an ordinary day starts as usual by getting up in the early morning to do exercise in public parks, preparing for a full day of working and studying, then travelling along crowed boulevards or narrow streets filled with motor scooters and returning home after a busy day. They usually live in large houses, or high-rise apartment blocks or even in a small rental room equipped with modern facilities, like the Internet, telephone, television, and so on. Industrialization and modernization as well as global integration have big impact on lifestyle in the cities. The most noticeable impact is the Western style of clothes. The "Ao dai” - Vietnamese traditional clothes are no longer regularly worn in Vietnamese women's daily life. Instead, jeans, T-shirts and fashionable clothes are widely most important reason why people move to the city is that ………….A to look for a better life B to look for a complicated life Unlike life in the countryside which is often considered to be simple and traditional, life in the city is modern and complicated. People, from different regions, move to the cities in the hope of having a better life for them and their children. The inhabitants in city work as secretaries, businessmen, teachers, government workers, factory workers and even street vendors or construction workers. The high cost of living requires city dwellers, especially someone with low income, to work harder or to take a part-time job. For many people, an ordinary day starts as usual by getting up in the early morning to do exercise in public parks, preparing for a full day of working and studying, then travelling along crowed boulevards or narrow streets filled with motor scooters and returning home after a busy day. They usually live in large houses, or high-rise apartment blocks or even in a small rental room equipped with modern facilities, like the Internet, telephone, television, and so on. Industrialization and modernization as well as global integration have big impact on lifestyle in the cities. The most noticeable impact is the Western style of clothes. The "Ao dai” - Vietnamese traditional clothes are no longer regularly worn in Vietnamese women's daily life. Instead, jeans, T-shirts and fashionable clothes are widely to the passage, the city life can offer city dwellers all of the following things EXCEPT A friendly communication with neighbours C a variety of jobs in different fields Unlike life in the countryside which is often considered to be simple and traditional, life in the city is modern and complicated. People, from different regions, move to the cities in the hope of having a better life for them and their children. The inhabitants in city work as secretaries, businessmen, teachers, government workers, factory workers and even street vendors or construction workers. The high cost of living requires city dwellers, especially someone with low income, to work harder or to take a part-time job. For many people, an ordinary day starts as usual by getting up in the early morning to do exercise in public parks, preparing for a full day of working and studying, then travelling along crowed boulevards or narrow streets filled with motor scooters and returning home after a busy day. They usually live in large houses, or high-rise apartment blocks or even in a small rental room equipped with modern facilities, like the Internet, telephone, television, and so on. Industrialization and modernization as well as global integration have big impact on lifestyle in the cities. The most noticeable impact is the Western style of clothes. The "Ao dai” - Vietnamese traditional clothes are no longer regularly worn in Vietnamese women's daily life. Instead, jeans, T-shirts and fashionable clothes are widely is the main idea of the passage?B people do morning exercise in public parks because they have much free people leave the countryside because life there is most of the urban dwellers have low income. Unlike life in the countryside which is often considered to be simple and traditional, life in the city is modern and complicated. People, from different regions, move to the cities in the hope of having a better life for them and their children. The inhabitants in city work as secretaries, businessmen, teachers, government workers, factory workers and even street vendors or construction workers. The high cost of living requires city dwellers, especially someone with low income, to work harder or to take a part-time job. For many people, an ordinary day starts as usual by getting up in the early morning to do exercise in public parks, preparing for a full day of working and studying, then travelling along crowed boulevards or narrow streets filled with motor scooters and returning home after a busy day. They usually live in large houses, or high-rise apartment blocks or even in a small rental room equipped with modern facilities, like the Internet, telephone, television, and so on. Industrialization and modernization as well as global integration have big impact on lifestyle in the cities. The most noticeable impact is the Western style of clothes. The "Ao dai” - Vietnamese traditional clothes are no longer regularly worn in Vietnamese women's daily life. Instead, jeans, T-shirts and fashionable clothes are widely and modernization may lead to A some changes in the fact that women no longer wear ao the disappearance of Western-styled clothes. Unlike life in the countryside which is often considered to be simple and traditional, life in the city is modern and complicated. People, from different regions, move to the cities in the hope of having a better life for them and their children. The inhabitants in city work as secretaries, businessmen, teachers, government workers, factory workers and even street vendors or construction workers. The high cost of living requires city dwellers, especially someone with low income, to work harder or to take a part-time job. For many people, an ordinary day starts as usual by getting up in the early morning to do exercise in public parks, preparing for a full day of working and studying, then travelling along crowed boulevards or narrow streets filled with motor scooters and returning home after a busy day. They usually live in large houses, or high-rise apartment blocks or even in a small rental room equipped with modern facilities, like the Internet, telephone, television, and so on. Industrialization and modernization as well as global integration have big impact on lifestyle in the cities. The most noticeable impact is the Western style of clothes. The "Ao dai” - Vietnamese traditional clothes are no longer regularly worn in Vietnamese women's daily life. Instead, jeans, T-shirts and fashionable clothes are widely word "impact" in paragraph 2 is closest in meaning to .I don’t have a map, so I can’t show you the I would show you the way if I had a map. B Unless you give me a map, I won’t show you the I would have a map if I showed you the way. D Unless you have a map, I can show you the of his tiredness, Nam couldn't finish his Nam couldn't finish his homework because he was Nam couldn't finish his homework because he is Nam could finish his homework, so he was tired. D Nam couldn't finish his homework because he was a pity that this school year will not finish as I wish that this school year would finish as plannedB I wish that this school year finished as planned. C I wish that this school year will finish as I wish that this school year would not finish as is better at English than Linh doesn't learn English so well as Nam Nam learns English worse than Nam isn’t as good at English as Linh isn’t as bad at English as took shelter in a store …………. the rainstorm. I’m fluent …………..three letter A, B, C, or D to indicate the word OPPOSITE in meaning to the underlined petrol prices keep going up like this, I’ll have to use a bicycle. Peter “I'm taking my TOEFL test tomorrow.”Daisy “…………..”Have you ever considered…………….a pharmacist?She……….. a new computer last week, so did her friend. Some time ago, scientists began experiments to find out 16 ______ it would be possible to set up a “village” under the sea. History of Climate Change Interactive Timeline The tables below contain all of the items that are in the timeline above, organized by category greenhouse gases, modeling, past climate, impacts of climate change, and climate reports. If you have suggestions for additions to this timeline of the History of Climate Science Research, please contact us. Greenhouse Gases and the Greenhouse Effect Date Event 1640 Carbon Dioxide Discovered Johann Baptista van Helmolt, Flemish alchemist, determined that air is a mixture of gases. He studied carbon dioxide, which he called the “spirit of wood” because it was given off when wood was burned. In an experiment, he burned coal to see how much carbon dioxide it added to the air. 1754 First Carbon Dioxide Detector Joseph Black, a medical student in Edinburgh, figured out that limewater can be used as a carbon dioxide CO2 detector. He observed that the normally clear liquid turned milky when exposed to "fixed air," which is what he called CO2. He started measuring the gas everywhere with his limewater, and found that it was released from mineral water, fermenting yeast, burning coal and oil, cremating corpses, and human exhalation. The limewater instrument was later improved by Lord Cavendish, and became known as the Cavendish Apparatus. Learn more The Discovery of the Greenhouse Effect 1760 Industrial Revolution Begins Since the start of the Industrial Revolution, the way people live and work has changed dramatically as manufacturing expanded. Over time, the amount of fossil fuels burned increased, which has increased the amount of carbon dioxide CO2 in the atmosphere . Before the Industrial Revolution, there was approximately 280 parts per million ppm of CO in the air. Today, that amount is over 400 ppm. 1824 Describing Earth's Atmosphere as a Greenhouse Jean-Baptiste-Joseph Fourier, a mathematician working for Napoleon, was the first to describe how Earth's atmosphere retains warmth on what would otherwise be a very cold planet.. To help explain the concept, he compared the atmosphere to the glass walls of a greenhouse. Learn more The Discovery of the Greenhouse Effect 1856 Discovering Gases That Trap Heat Eunice Foote, American scientist, discovered that carbon dioxide and water vapor cause air to warm in sunlight. In 1856, she presented her findings at the meeting of the American Association for the Advancement of Science AAAS. “A paper was read before the late meeting of the Scientific Association, by Prof. Henry for Mrs. Eunice Foot, detailing her experiments to determine the effects of the sun’s rays on different gases,” noted an 1856 article in Scientific American. 1859 Testing the Heat-Trapping Ability of Gases John Tyndall, British physicist, tested the gases in the atmosphere to find out which are responsible for the greenhouse effect. He found that nitrogen and oxygen, which make up almost all of the atmosphere, have no ability to trap heat, but that three gases present in smaller quantities do carbon dioxide, ozone, and water vapor. Tyndall speculated that if the amounts of these gases dropped, it would chill the Earth. 1896 Connecting Coal, Carbon Dioxide, and Climate Swedish chemist Svante Arrhenius recognized that burning coal could increase carbon dioxide and warm the climate. He estimated how much carbon dioxide the ocean could absorb. In an 1896 lecture, Arrhenius noted that it was not yet possible to calculate how fast temperature was rising. He also speculated that warming would be beneficial as people in the future "might live under a milder sky and in less barren surroundings." Learn more Svante Arrhenius and the Greenhouse Effect [.pdf] 1938 Increasing Carbon Dioxide and Increasing Temperatures British coal engineer George Callendar compiled all carbon dioxide measurements made over the previous 100 years and found that the amount of CO2 was increasing. He also found that temperatures were rising. His conclusion was that this was a good thing, that "the return of the deadly glaciers should be delayed indefinitely." Read his 1949 article Can Carbon Dioxide Influence Climate? 1957 Our Unintended Experiment Roger Revelle, oceanographer, and Hans Suess, Austrian-born chemist, realizing that carbon dioxide from industrial sources must be building up in the atmosphere, wrote in 1957 "Thus human beings are now carrying out a large scale geophysical experiment of a kind that could not have happened in the past nor be reproduced in the future." 1958 Climate Science on Television The Bell Telephone Science Hour addressed how our actions could be changing Earth's climate. "Even now, [we] may be unwittingly changing the world's climate through the waste products of [our] civilization," said the narrator. "Due to our release from factories and automobiles every year of more than six billion tons of carbon dioxide, which helps the air absorb heat from the Sun, our atmosphere seems to be getting warmer." 1958 Daily Measurements of Carbon Dioxide Charles Keeling started making daily measurements of the amount of carbon dioxide in the air atop Mauna Loa in Hawaii. That first March day, he found 313 parts per million ppm of carbon dioxide in the air. The measurements, which are still make each day, reached 400 ppm on May 9, 2013, and continue to climb. 1988 Climate in Congress NASA climate scientist James Hansen testified before the Senate Energy and Natural Resources Committee stating that climate was warming, greenhouse gases are responsible for the warming, and we are responsible for the growth in these gases. 1992 An Increasingly Acidic Ocean scientists Stephen V. Smith and Buddemeier pointed out that more carbon dioxide CO2 in the ocean could be a problem for coral reefs. Later experiments confirmed their hypothesis that CO2 makes seawater slightly acidic, which makes it difficult for corals and other animals to build reefs. Today at NCAR, scientist Joanie Kleypas builds on their work, researching the impacts of acidic oceans on marine life. 2016 CO2 Stays Above 400 ppm Year-round September is typically when carbon dioxide is at a minimum in its annual cycle. September 2016 was the first time that minimum level was over 400 parts per million. Before large-scale burning of fossil fuels, CO2 levels were about 280 ppm. Learn more The World Passes 400 PPM Threshold. Permanently Modeling the Earth and Future Climate Date Event 1960s Simple Models to Study the Atmosphere Syukuro Manabe and Richard Wetherald developed a basic model of the atmosphere at NOAA. With the model, they found that more carbon dioxide in the atmosphere causes higher temperatures at Earth's surface. This simple model was the first step toward development of complex Earth system models. Read their 1967 paper Thermal Equilibrium of the Atmosphere with a Given Distribution of Relative Humidity “Greenhouse gases are the second most important factor for climate, after the Sun.” -Syukuro Manabe 1960s Modeling the Whole Atmosphere At the National Center for Atmospheric Research, scientists Akira Kasahara and Warren Washington developed a model of the whole atmosphere called a general circulation model. At first, they ran the model on a CDC 3600, a computer that filled a room yet only had a single processor. “We pretty much beat the thing up because we were running a general circulation model on it 24 hours a day, seven days a week,” said Washington. “They didn’t anticipate for people to use computers in that way.” Learn more NCAR's CDC 3600 1975-1985 Better Models and Faster Computers More powerful supercomputers like the Cray 1A allowed researchers to develop more complex models that included the dynamics of both the atmosphere and ocean. Their results confirmed those from earlier models climate is warming because of the greenhouse gases added to the atmosphere. Learn more NCAR's Cray 1A 1990s Climate System Models New models were developed to include how the ocean, land, sea ice, and atmosphere interact to affect the climate. At the end of the decade, the National Center for Atmospheric Research ran a new model, the Community Climate System Model CCSM, on its latest supercomputer to learn more about interactions in Earth's climate system. Learn more 1998 special issue on CCSM results in the Journal of Climate 1990 Regional Climate Modeling Robert Dickinson led a team to create a regional climate model for the western United States in 1989 and, in 1990, Filippo Giorgi simulated regional climate using a model nested in a general circulation model GCM. Regional climate modeling has allowed predictions of how global climate change impacts local areas. Learn more Thirty years of regional climate modeling 2010 Earth System Models Provide Improved Understanding Models that can include dynamics of the Earth system, including feedbacks and biogeochemical cycling, gave a more detailed view of climate change and its impacts. Advancements in modeling at NCAR, NOAA, and other research centers around the world have ushered in a new era in understanding of our complex planet. Learn more Community Earth System Model at NCAR NOAA’s First Earth System Model 2020 Climate Models are Getting Future Warming Projections Right Climate models have been making predictions since the 1970s, but are the predictions right? To find out, scientists ran 17 global climate models and compared the results with observed temperatures over the past half-century. Fourteen of the models predicted past temperatures accurately, which gives scientists confidence in the models’ ability to correctly project future warming. Learn more Climate Models are Getting Future Warming Right Studying Past Climate Date Event 1891 Climate Recorded in Dust Self-taught geologist John Hardcastle realized that large deposits of wind-blown dust known as loess in New Zealand record changes in climate from Ice Ages to warm periods in between. "This growing dust heap played the part of an observant bystander, taking notes of certain climatic phenomena as they successively arose." —John Hardcastle Learn more John Hardcastle on Glacier Motion and Glacial Loess 1966 Ice Core Uncovers 8,200 Years of Climate At Camp Century, Greenland, an ice core was extracted that showed 8,200 years of annual snow accumulation as thin layers in the ice. The thin layers of ice allowed scientists to reconstruct ancient climate using an ice core for the first time. Learn more Core of climate history 1966 Climate History from the Ocean Floor In 1966, a shipbuilding company began making a ship with a drill rig on top for the Deep Sea Drilling Project, a project based at the Scripps Institute of Oceanography in San Diego, California. The drill rig would allow scientists to collect cores from the ocean floor around the world that contain layers of sediments – a record of ancient changes in climate over millions of years. Today the Integrated Ocean Drilling Program continues to collect these deepsea records. Learn more Integrated Ocean Drilling Program 1985 Drilling 150,000 Years Deeper into the Ice Ice cores extracted from Antarctic ice in 1985 showed carbon dioxide and temperature had gone up and down together in wide swings over the past 150,000 years, the same relationship that computer models suggested. Learn more Core of climate history 2005 Finding Really Old Ice and its Climate History A deep ice core from East Antarctica helped us understand how climate has changed over the past 650,000 years. Studying ancient air bubbles in the ice, scientists have learned details about the ancient atmosphere, including that levels of carbon dioxide are unusually high today compared to past interglacial periods. Learn more Core of climate history 2012 Indigenous Climate Knowledge Since 2012, the Rising Voices program has brought indigenous knowledge and western science together to improve understanding of climate change and other types of science and to develop strategies for resilient and sustainable communities. "We need to appreciate the experience and knowledge that has been transferred from generation to generation to generation in Native American communities." - Bob Gough Learn more Rising Voices at NCAR The Science of Climate Impacts Date Event 1950s Shrinking Arctic Sea Ice Measurements since the 1950s indicate that the amount of sea ice in the Arctic has been declining. The Arctic is projected to have no summer ice cover by the middle of this century. Check on sea ice at the National Snow and Ice Data Center. 1950s-1970s Air Pollution Dampens Warming Aerosols, emitted into the atmosphere from smokestacks and tailpipes, caused a slight cooling of climate, which fueled speculation that we could enter an Ice Age. As countries passed clean air legislation, aerosol pollution decreased and climate warming continued. 2003 Heat Wave Linked to Climate Change Researchers determined that climate change played a large role in the 2003 heatwave in Europe, which resulted in more than 30,000 deaths. Learn more European Summer Heat Wave of 2003 2006 Economic Impacts of Climate Change The Stern Review described the economic impacts of climate change, finding that mitigating reducing the amount of greenhouse gas emissions and adapting making changes to the way we live would be much less expensive than the cost of trying to recover from the disastrous impacts of climate change in the future. Read the report The Stern Review on the Economics of Climate Change 2007-2008 Studying Impacts in the Polar Regions During International Polar Year which was actually two years' long 2007-2008, scientists documented numerous impacts of climate change on the polar regions, which are warming more rapidly than other areas of Earth. Impacts included melting ice, thawing permafrost, and changes in ecosystems. They found that changes were especially pronounced in the Arctic. 2011 The Effect of Climate Change on Extreme Weather A new branch of climate science, called attribution research, formed to study how global climate change affects extreme weather events such as heat waves, hurricanes, floods, and droughts. Each year since 2011, the Bulletin of the American Meteorological Society has issued a special report about extreme weather events during the past year and how the risk of severe weather has been altered by climate change. Read the report Explaining Extreme Events from a Climate Perspective 2019 Dwindling Biodiversity With Earth system models, scientists are now able to study how species and ecosystems around the world are likely to be affected by climate change and other human impacts. According to a 2019 United Nations report, climate change and other human impacts such as pollution and land use are threatening species worldwide. "Around 1 million species already face extinction, many within decades, unless action is taken," according to the report. Read the report United Nations 2019 Report Learn how NCAR is modeling Western Pacific coral reefs 2021 2020 Ties with 2016 as the Warmest Year On Record 2016 and 2020 tied as the warmest years on record, according to 2021 reports. Scientists studying long-term temperature records found that the 10 warmest years through 2020 all occurred since 2000. From NASA Goddard Institute for Space Studies Director Gavin Schmidt, “...As the human impact on the climate increases, we have to expect that records will continue to be broken.“ Learn more Read the article NASA Global Temperature Analysis More information Global Temperature Rankings The Intergovernmental Panel on Climate Change IPCC Date Event 1988 The Intergovernmental Panel on Climate Change IPCC Formed The IPCC was formed by the World Meteorological Organization and the United Nations to review the latest climate science every few years and help governments around the world understand what we know about climate change, its impacts, and efforts to adapt and mitigate. Learn more About the IPCC 1990 First Climate Assessment Report by the IPCC Published in 1990, the IPCC's First Assessment Report stated that it was certain that "human activities are substantially increasing the atmospheric concentrations of greenhouse gases."According to the report, greenhouse gas increases had caused temperature to increase by to Celsius - Fahrenheit over the past century and would cause global average temperature to warm about 1°C by 2025 and 3°C by 2100. Projections for regional temperature and precipitation changes were highly uncertain. Learn more Read the Overview of the IPCC First Assessment Report [.pdf] 1995 Evidence Suggests Human Influence on Climate The Second Assessment Report of the IPCC provided key information that led to the development of the Kyoto Protocol in 1997."Considerable progress has been made in the understanding of climate change science since 1990," wrote the authors. Acknowledging that global climate had changed over the past century, the authors noted that regional climate change was also evident and that "global sea level has risen by 10 - 25 centimeters 4-10 inches over the past 100 years." Learn more About the Kyoto Protocol 2001 New and Stronger Evidence That We Are Causing Climate Change According to the Third Assessment Report of the Intergovernmental Panel on Climate Change IPCC, "there is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities." Climate models projected that, between 1990 and 2100, Earth's atmosphere would warm by to to depending on how much greenhouse gas humans emitted during that time. "The projected rate of warming is very likely to be without precedent during at least the last 10,000 years," noted the authors. The report outlined the impacts of warming, such as changing precipitation patterns, melting glaciers, and rising sea levels, as well as changes to biodiversity, economic systems, and human health. 2007 Climate Change Indisputable The IPCC Fourth Assessment Report noted that human-caused greenhouse gas emissions had increased 70% between 1970 and 2004 and the effects of climate change were becoming apparent. "Warming of the climate system is unequivocal," wrote the authors of the 2007 report, "as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average sea level." "Anthropogenic [human-caused] warming could lead to some impacts that are abrupt or irreversible," they warned. "More extensive adaptation than is currently occurring is required to reduce vulnerability to climate change." 2014 Emissions Are the Highest in History The IPCC 5th Assessment Report noted that our influence on climate is clear and "recent anthropogenic emissions of greenhouse gases are the highest in history." The report's findings led to the Paris Climate Accord, in which nearly all of the world's countries 174 countries in total committed to actions limiting warming to below 2° Celsius Fahrenheit in an effort to avoid the most catastrophic impacts. The United States announced in 2017 that it would back out of the agreement. Learn more Paris Climate Accord 2022 Adverse Impacts are Beyond Natural Climate Variability The Sixth Assessment Report highlights the impacts of human-induced climate change, including more frequent and intense extreme events. The changes have caused widespread adverse impacts and damages to nature and people, beyond what would be expected from natural climate variability. Learn more IPCC Summary for Policymakers Headline Statements ScienceNot Exactly Rocket ScienceIn 1958, a young scientist called Stanley Miller electrified a mixture of simple gases, designed to mimic the atmosphere of our primordial lifeless planet. It was a sequel to one of the most evocative experiments in history, one that Miller himself had carried five years earlier. But for some reason, he never finished his follow-up. He dutifully collected his samples and stored them in vials but, whether for ill health or dissatisfaction, he never analysed vials languished in obscurity, sitting unopened in a cardboard box in Miller’s office. But possessed by the meticulousness of a scientist, he never threw them away. In 1999, the vials changed owners. Miller had suffered a stroke and bequeathed his old equipment, archives and notebooks to Jeffrey Bada, one of his former students. Bada only twigged to the historical treasures that he had inherited in 2007. “Inside, were all these tiny glass vials carefully labeled, with page numbers referring Stanley’s laboratory notes. I was dumbstruck. We were looking at history,” he said in a New York Times then, Miller was completely incapacitated. He died of heart failure shortly after, but his legacy continues. Bada’s own student Eric Parker has finally analysed Miller’s samples using modern technology and published the results, completing an experiment that began 53 years conducted his original 1953 experiment as a graduate student, working with his mentor Harold Urey. It was one of the first to tackle the seemingly insurmountable question of how life began. In their laboratory, the pair tried to recreate the conditions on early lifeless Earth, with an atmosphere full of simple gases and laced with lightning storms. They filled a flask with water, methane, ammonia and hydrogen and sent sparks of electricity through result, both literally and figuratively, was lightning in a bottle. When Miller looked at the samples from the flask, he found five different amino acids – the building blocks of proteins and essential components of relevance of these results to the origins of life is debatable, but there’s no denying their influence. They kicked off an entire field of research, graced the cover of Time magazine and made a celebrity of Miller. Nick Lane beautifully describes the reaction to the experiment in his book, Life Ascending “Miller electrified a simple mixture of gases, and the basic building blocks of life all congealed out of the mix. It was as if they were waiting to be bidden into existence. Suddenly the origin of life looked easy.”Over the next decade, Miller repeated his original experiment with several twists. He injected hot steam into the electrified chamber to simulate an erupting volcano, another mainstay of our primordial planet. The samples from this experiment were among the unexamined vials that Bada inherited. In 2008, Bada’s student Adam Johnson showed that the vials contained a wider range of amino acids than Miller had originally reported in also tweaked the gases in his electrified flasks. He tried the experiment again with two newcomers – hydrogen sulphide and carbon dioxide – joining ammonia and methane. It would be all too easy to repeat the same experiment now. But Parker and Bada wanted to look at the original samples that Miller had himself collected, if only for their “considerable historical interest”.Using modern techniques, around a billion times more sensitive than those Miller would have used, Parker identified 23 different amino acids in the vials, far more than the five that Miller had originally described. Seven of these contained sulphur, which is either a first for science or old news, depending on how you look at it. Other scientists have since produced sulphurous amino acids in similar experiments, including Carl Sagan. But unbeknownst to all of them, Miller had beaten them to it by several years. He had even scooped himself – it took him till 1972 to publish results where he produced sulphur amino acids!The amino acids in Miller’s vials all come in an equal mix of two forms, each the mirror image of the other. You only see that in laboratory reactions – in nature, amino acids come almost entirely in one version. As such, Parker, like Miller before him, was sure that the amino acids hadn’t come from a contaminating source, like a stray bacterium that had crept into the then, a young and violent planet, wracked with exploding volcanoes, noxious gases and lightning strikes. These ingredients combined to brew a “primordial soup”, fashioning the precursors of life in pools of water. On top of that, meteorites raining down from space could have added to the accumulating molecules. After all, Parker found that the amino acid cocktail in Miller’s samples is very similar to that found on the Murchison meteorite, which landed in Australia in are powerful images, so why aren’t people more excited? Echoing many sources I spoke to, Jim Kasting, who studies the evolution of Earth’s atmosphere, said, “I am underwhelmed by it.” The main problem with the study is that Miller was probably wrong about the conditions on early analysing ancient rocks, scientists have since found that Earth was never particularly teeming in hydrogen-rich gases like methane, hydrogen sulphide or hydrogen itself. If you repeat Miller’s experiment with a more realistic mixture – heavy in carbon dioxide and nitrogen, with just trace amounts of other gases – you’d have a hard time finding amino acids in the resulting accepts the problem, but he suggests that a few specific places on the planet may have had the right conditions. Exploding volcanoes, for example, throw up masses of sulphurous compounds, as well as methane and ammonia. These gases, belched forth into lightning storms, could have produced amino acids that rained out and gathered in tidal pools. But Kasting still isn’t convinced. “Even then the reduced gases would not be as concentrated as they are in this experiment.”Even if our young planet had the right conditions to produce amino acids, that’s a less impressive feat than it appeared in the 1950s. “Amino acids are old hat and are a million miles from life,” says Nick Lane. Indeed, as Miller’s experiments showed, it’s not difficult to create amino acids. The far bigger challenge is to create nucleic acids – the building blocks of molecules like RNA and DNA. The origin of life lies in the origin of these “replicators”, molecules that can make copies of themselves. Lane says, “Even if you can make amino acids and nucleic acids under soup conditions, it has little if any bearing on the origin of life.”The problem is that replicators don’t spontaneously emerge from a mixture of their building blocks, just as you wouldn’t hope to build a car by throwing some parts into a swimming pool. Nucleic acids are innately “shy”. They need to be strong-armed into forming more complex molecules, and it’s unlikely that the odd bolt of lightning would have been enough. The molecules must have been concentrated in the same place, with a constant supply of energy and catalysts to speed things up. “Without that lot, life will never get started, and a soup can’t provide much if any of that,” says vents are a better location for the origins of life. Deep under the ocean’s surface, these rocky chimneys spew out superheated water and hydrogen-rich gases. Their rocky structures contain a labyrinth of small compartments that could have concentrated life’s building blocks into dense crowds, and minerals that would have catalysed their get-togethers. Far away from visions of languid soups, these churning environments are the current best guess for the site of life’s Miller’s iconic experiment, and its now-completed follow-ups, probably won’t lay out the first steps of life. As Adam Rutherford, who is writing a book on the origin of life, says, “It’s really a historical piece, like finding that Darwin had described a Velociraptor in one of his notebooks.”If anything, the analysis of Miller’s vials is a testament to the value of meticulous scientific work. Here was a man who prepared his samples so cleanly, who recorded his notes so thoroughly, and who stored everything so carefully, that his contemporaries could pick up where he left off five decades Parker, Cleaves, Dworkin, Glavin, Callahan, Aubrey, Lazcano & Bada. 2011. Primordial synthesis of amines and amino acids in a 1958 Miller H2S-rich spark discharge experiment. PNAS by Carlos Gutierrez and Marco FulleMore on origins A possible icy start for lifeTree or ring the origin of complex cellsThe origin of complex life – it was all about energy Some time ago, scientists began experiments to find out 31 ______ it would be possible to set up a“village” under the sea. A special room was built and lowered 32 ______ the water of Port Sudan in theRed Sea. For 29 days, five men lived at a depth of 40 feet. At a 33 ______ lower level, another two diversstayed for a week in a smaller “house”. On returning to the surface, the men said that they had experiencedno difficulty in breathing and had 34 ______ many interesting scientific observations. The captain of theparty, Commander Cousteau, spoke of the possibility of 35 ______ the seabed. He said that somepermanent stations were to be set up under the sea, and some undersea farms would provide food for thegrowing population of the 31A. whichB. whatC. howD. whetherQuestion 32A. underneathB. intoC. downD. belowQuestion 33A. anyB. moreC. muchD. someQuestion 34A. madeB. exercisedC. caughtD. doneQuestion 35A. implantingB. transplanting C. growingD. cultivatingRead the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correctanswer to each of the questions from 36 to the most famous film commenting on the twentieth-century technology is Modern Times, madein 1936. Charlie Chaplin was motivated to make the film by a reporter who, while interviewing him,happened to describe the working conditions in industrial Detroit. Chaplin was told that healthy young farm30 ĐỀ TRỌNG TÂMĐăng kí tại fanpage Tài liệu KYS4boys were lured to the city to work on automotive assembly lines. Within four or five years, these youngmen’s health was destroyed by the stress of work in the film opens with a shot of a mass of sheep making their way down a crowded the film shifts to a scene of factory workersjostling one anotheron their way to a the rather bitter note of criticism in the implied comparison is not sustained. It is replaced by agentle note of satire. Chaplin prefers to entertain rather than of factory interiors account for only about one-third of Modern Times, but they contain some ofthe most pointed social commentary as well as the most comic situations. No one who has seen the filmcan ever forget Chaplinvainlytrying to keep pace with the fast-moving conveyor belt, almost losing hismind in the process. Another popular scene involves an automatic feeding machine brought to the assemblyline so that workers need not interrupt their labor to eat. The feeding machine malfunctions, hurling foodat Chaplin, who is strapped in his position on the assembly line and cannot escape. This serves to illustratepeople’s utter helplessness in the face of machines that are meant to serve their basic needs.

some time ago scientists began experiments