TUNIS, April 4 -- China will offer five scholarships to Arabs on the Chinese BeiDou Navigation Satellite System (BDS). A statement after the second China-Arab States BDS Cooperation Forum held in the Tunisian capital Tunis said Tuesday that the BDS will offer the scholarships and provide more services to countries and regions involved in the China-proposed Belt and Road Initiative. The statement added that 18 short-term training courses have been offered since 2012 on Global Navigation Satellite System (GNSS) inside and outside China. China's BDS is recognized globally along with the US GPS, Russian GLONASS and European Galileo systems. Some 800 people received training earlier and some Chinese experts were sent to Tunisia, Egypt, Sudan, Morocco, Algeria and other Arab countries to provide training courses on BDS. The China-Arab States BDS/GNSS Center, the first overseas BDS center, was set up in Tunis in 2018 to showcase the BDS technology and promote international exchanges and cooperation on the field. The BDS, which went into trial operation in 2011 and started global service in later 2018, is a navigation satellite system independently developed by China.
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WASHINGTON, March 26 -- A major Greenland glacier that was one of the fastest shrinking ice and snow masses on Earth is growing again, a new NASA study finds. The Jakobshavn glacier around 2012 was retreating about 1.8 miles (3 kilometers) and thinning nearly 130 feet (almost 40 meters) annually. But it started growing again at about the same rate in the past two years, according to a study in Monday’s Nature Geoscience. “That was kind of a surprise. We kind of got used to a runaway system,” said Geological Survey of Denmark and Greenland ice and climate scientist Jason Box. “The good news is that it’s a reminder that it’s not necessarily going that fast. But it is going.” Box, who wasn’t part of the study, said Jakobshavn is “arguably the most important Greenland glacier because it discharges the most ice in the northern hemisphere. For all of Greenland, it is king.” A natural cyclical cooling of North Atlantic waters likely caused the glacier to reverse course, said study lead author Ala Khazendar, a NASA glaciologist on the Oceans Melting Greenland (OMG) project. Khazendar and colleagues say this coincides with a flip of the North Atlantic Oscillation — a natural and temporary cooling and warming of parts of the ocean that is like a distant cousin to El Nino in the Pacific. The water in Disko Bay, where Jakobshavn hits the ocean, is about 3.6 degrees cooler (2 degrees Celsius) than a few years ago, study authors said. While this is “good news” on a temporary basis, this is "real good news" on the long term because it tells scientists that ocean temperature is a bigger player in glacier retreats and advances than previously thought, said NASA climate scientist Josh Willis, a study co-author. Over the decades the water has been and will be warming from man-made climate change, he said, noting that about 90 percent of the heat trapped by greenhouse gases goes into the oceans. “In the long run we’ll probably have to raise our predictions of sea level rise again,” Willis said. Think of the ocean temperatures near Greenland like an escalator that’s rising slowly from global warming, Khazendar said. But the natural North Atlantic Oscillation sometimes is like jumping down a few steps or jumping up a few steps. The water can get cooler and have effects, but in the long run it is getting warmer and the melting will be worse, he said. Four outside scientists said the study and results make sense. University of Washington ice scientist Ian Joughin, who wasn’t part of the study and predicted such a change seven years ago, said it would be a “grave mistake” to interpret the latest data as contradicting climate change science. What’s happening, Joughin said, is “to a large extent, a temporary blip. Downturns do occur in the stock market, but overall the long term trajectory is up. This is really the same thing.” ROTTERDAM, March 18 -- Nuclear energy produces carbon-free electricity, and the United States has used nuclear energy for decades to generate baseline power. Nuclear energy, however, carries a dreaded stigma. After disasters such as Chernobyl, Three Mile Island, and Fukishima, the public is acutely aware of the potential, though misguided, dangers of nuclear energy. The cost of nuclear generation is on the rise–a stark contrast to the decreasing costs of alternative energy forms such as solar and wind, which have gained an immense amount of popularity recently. This trend could continue until market forces make nuclear technology obsolete. Into this dynamic comes a resurgence in nuclear technology: liquid fluoride thorium reactors, or LFTRs (“lifters”). A LFTR is a type of molten salt reactor, significantly safer than a typical nuclear reactor. LFTRs use a combination of thorium (a common element widely found in the earth) and fluoride salts to power a reactor. A typical arrangement for a modern thorium-based reactor resembles a conventional reactor, albeit with notable differences. First, thorium-232 and uranium-233 are added to fluoride salts in the reactor core. As fission occurs, heat and neutrons are released from the core and absorbed by the surrounding salt. This creates a uranium-233 isotope, as the thorium-232 takes on an additional neutron. The salt melts into a molten state, which runs a heat exchanger, heating an inert gas such as helium, which drives a turbine to generate electricity. The radiated salt flows into a post-processing plant, which separates the uranium from the salt. The uranium is then sent back to the core to start the fission process again.
Thorium reactors generate significantly less radioactive waste, and can re-use separated uranium, making the reactor self-sufficient once started. LFTRs are designed to operate as a low-pressure system unlike traditional high-pressure nuclear systems, which creates a safer working environments for workers who operate and maintain these systems. Additionally, the fluoride salts have very high boiling points, meaning even a large spike in heat will not cause a massive increase in pressure. Both of these factors greatly limit the chance of a containment explosion. LFTRs don’t require massive cooling, meaning they can be placed anywhere and can be air-cooled. If the core were to go critical, gravity would allow the heated, radiated salt to spill into passive via underground fail-safe containment chambers, capped by an ice plug that melts upon contact. LFTRs provide numerous benefits. Any leftover radioactive waste cannot be used to create weaponry. The fuel cost is significantly lower than a solid-fuel reactor. The salts cost roughly $150/kg, and thorium costs about $30/kg. If thorium becomes popular, this cost will only decrease as thorium is widely available anywhere in the earth’s crust. Thorium is found in a concentration over 500 times greater than fissile uranium-235. Historically, thorium was tossed aside as a byproduct of rare-earth metal mining. With extraction, enough thorium could be obtained to power LFTRs for thousands of years. For a 1 GW facility, material cost for fuel would be around $5 million. Since LFTRs use thorium in its natural state, no expensive fuel enrichment processes or fabrication for solid fuel rods are required, meaning the fuel costs are significantly lower than a comparable solid-fuel reactor. In an ideally working reactor, the post chemical reprocessing would allow a LFTR to efficiently consume nearly all of its fuel, leaving little waste or byproduct unlike a conventional reactor. Lastly, a thorium plant will operate at about 45 percent thermal efficiency, with upcoming turbine cycles possibly improving the overall efficiency to 50 percent or greater, meaning a thorium plant can be up to 20 percent more efficient than a traditional light-water reactor. LFTRs do present a few challenges. There are significant gaps in the research and necessary materials for LFTRs. The post-processing chemical facilities, which would separate uranium from the molten salts for re-use, haven’t been viably constructed yet. Each reactor would require some highly enriched uranium (such as uranium-235) to start the reactor, which is very expensive. Scientists suggest a $5 billion investment over the next five years could net a viable reactor solution in the United States, but with limited funding for thorium, it is difficult to see this vision come to fruition. Other countries have made preliminary investments towards building thorium reactors. The public stigma about nuclear is real, and that must be overcome first before lawmakers will take action, as money needs to be allocated for research and development to continue on LFTRs in the United States. Without public and scientific support, it will be difficult to move forward with this technology. Education is needed to help push the agenda for thorium, spread information about thorium-based reactors, and educate the public about their safety. Resources to learn more about thorium and LFTRs include websites such as The Independent Global Nuclear News Agency and World Nuclear News, or conferences such as the Thorium Energy Conference. Thorium reactors are a different way to generate electricity that could benefit the world. More efficient than their fossil fuel counterparts, safer than a conventional nuclear plant, and generating no carbon emissions as a byproduct, LFTRs are a viable solution for the future of our world’s energy needs. ROTTERDAM, March 14 -- If you've ever expressed the least bit of skepticism about environmentalist calls for making the vast majority of fossil fuel use illegal. You've probably heard the smug response: “97% of climate scientists agree with climate change” — which always carries the implication: Who are you to challenge them? The answer is: you are a thinking, independent individual--and you don’t go by polls, let alone second-hand accounts of polls; you go by facts, logic and explanation. Here are two questions to ask anyone who pulls the 97% trick. 1. What exactly do the climate scientists agree on? Usually, the person will have a very vague answer like "climate change is real." Which raises the question: What is that supposed to mean? That climate changes? That we have some impact? That we have a large impact? That we have a catastrophically large impact? That we have such a catastrophic impact that we shouldn't use fossil fuels? What you'll find is that people don't want to define what 97% agree on--because there is nothing remotely in the literature saying 97% agree we should ban most fossil fuel use. It’s likely that 97% of people making the 97% claim have absolutely no idea where that number comes from. If you look at the literature, the specific meaning of the 97% claim is: 97 percent of climate scientists agree that there is a global warming trend and that human beings are the main cause--that is, that we are over 50% responsible. The warming is a whopping 0.8 degrees over the past 150 years, a warming that has tapered off to essentially nothing in the last decade and a half. Even if 97% of climate scientists agreed with this, and even if they were right, it in no way, shape, or form would imply that we should restrict fossil fuels--which are crucial to the livelihood of billions. Because the actual 97% claim doesn’t even remotely justify their policies, catastrophists like President Obama and John Kerry take what we could generously call creative liberties in repeating this claim. On his Twitter account, President Obama tweets: “Ninety-seven percent of scientists agree: #climate change is real, man-made and dangerous.” Not only does Obama sloppily equate “scientists” with “climate scientists,” but more importantly he added “dangerous” to the 97% claim, which is not there in the literature. This is called the fallacy of equivocation: using the same term (“97 percent”) in two different ways to manipulate people. John Kerry pulled the same stunt when trying to tell the underdeveloped world that it should use fewer fossil fuels:
And let there be no doubt in anybody’s mind that the science is absolutely certain. . . 97 percent of climate scientists have confirmed that climate change is happening and that human activity is responsible. . . . . they agree that, if we continue to go down the same path that we are going down today, the world as we know it will change—and it will change dramatically for the worse. In Kerry’s mind, 97% of climate scientists said whatever Kerry wants them to have said. Bottom line: What the 97% of climate scientists allegedly agree on is very mild and in no way justifies restricting the energy that billions need. But it gets even worse. Because it turns out that 97% didn’t even say that. Which brings us to the next question: 2. How do we know the 97% agree? To elaborate, how was that proven? Almost no one who refers to the 97% has any idea, but the basic way it works is that a researcher reviews a lot of scholarly papers and classifies them by how many agree with a certain position. Unfortunately, in the case of 97% of climate scientists agreeing that human beings are the main cause of warming, the researchers have engaged in egregious misconduct. One of the main papers behind the 97 percent claim is authored by John Cook, who runs the popular website SkepticalScience.com, a virtual encyclopedia of arguments trying to defend predictions of catastrophic climate change from all challenges. Here is Cook’s summary of his paper: “Cook et al. (2013) found that over 97 percent [of papers he surveyed] endorsed the view that the Earth is warming up and human emissions of greenhouse gases are the main cause.” This is a fairly clear statement—97 percent of the papers surveyed endorsed the view that man-made greenhouse gases were the main cause—main in common usage meaning more than 50 percent. But even a quick scan of the paper reveals that this is not the case. Cook is able to demonstrate only that a relative handful endorse “the view that the Earth is warming up and human emissions of greenhouse gases are the main cause.” Cook calls this “explicit endorsement with quantification” (quantification meaning 50 percent or more). The problem is, only a small percentage of the papers fall into this category; Cook does not say what percentage, but when the study was publicly challenged by economist David Friedman, one observer calculated that only 1.6 percent explicitly stated that man-made greenhouse gases caused at least 50 percent of global warming. Where did most of the 97 percent come from, then? Cook had created a category called “explicit endorsement without quantification”—that is, papers in which the author, by Cook’s admission, did not say whether 1 percent or 50 percent or 100 percent of the warming was caused by man. He had also created a category called “implicit endorsement,” for papers that imply (but don’t say) that there is some man-made global warming and don’t quantify it. In other words, he created two categories that he labeled as endorsing a view that they most certainly didn’t. The 97 percent claim is a deliberate misrepresentation designed to intimidate the public—and numerous scientists whose papers were classified by Cook protested: “Cook survey included 10 of my 122 eligible papers. 5/10 were rated incorrectly. 4/5 were rated as endorse rather than neutral.” —Dr. Richard Tol “That is not an accurate representation of my paper . . .” —Dr. Craig Idso “Nope . . . it is not an accurate representation.” —Dr. Nir Shaviv “Cook et al. (2013) is based on a strawman argument . . .” —Dr. Nicola Scafetta Think about how many times you hear that 97 percent or some similar figure thrown around. It’s based on crude manipulation propagated by people whose ideological agenda it serves. It is a license to intimidate. It’s time to revoke that license. THE HAGUE, March 13 -- Proposals to fight climate change will cost the Netherlands around 5.2 billion euros ($6 billion) over the next decade but will not be enough to meet its emission reduction goals, the government’s top advisory body said on Wednesday. The Netherlands is one of the most polluting countries in Europe, with higher CO2 emissions per citizen and a lower use of sustainable energy than almost everywhere in the European Union. The Dutch government is expected to decide by the end of April on what action to take to tackle climate change after a consultation led to a series of measures proposed by businesses, activists and other groups. Government adviser CPB said these are expected to reduce gross domestic product by around 0.5 percent by 2030, but will most likely not enable the government to meet its target of reducing CO2 emissions by 49 percent in 2030 from 1990 levels. Dutch CO2 emissions are expected to be 21 percent lower than in 1990 next year, missing the goal of a 25 percent reduction which was ordered by a Dutch court last year. “These policies could significantly stimulate the energy transition, but a lot still needs to be done”, CPB said of the around 130 measures which were put forward. These include higher taxes on the use of gas for heating and on airline tickets, subsidies on electrical cars, increased use of wind and solar power, and incentives for industry to cut emissions and homeowners to better insulate their houses. Of the total cost, around 3.2 billion euros would have to be paid by households, CPB said. MURMANSK, March 13 -- The Northern Fleet’s experts made 34 geographic discoveries in the Arctic as part of scientific activity in recent years, Northern Fleet’s commander Admiral Nikolai Yevmenov told journalists on Wednesday. "The Northern Fleet’s hydrographic vessels Gorizont, Vizir and Senezh made 34 geographic discoveries during research voyages to the Arctic," the commander said. The fleet said earlier that the Northern Fleet renewed its scientific-research activity in the Arctic in 2014. Since then, the Northern Fleet’s naval surveyors discovered and described one strait, 12 islands, 14 capes and six bays, and one expedition discovered the disappearance of an island. In 2018, the Northern Fleet carried out an unparalleled combined expedition to the Novaya Zemlya Archipelago with support from the Russian Geographical Society. A number of historic experiments on the reconstruction of the pioneering explorers’ routes was carried out during this expedition. This year the Northern Fleet plans to carry out expeditions to the islands of Franz Josef Land and Sredniy Island on the Severnaya Zemlya archipelago and continue expedition activity on Novaya Zemlya in cooperation with the expeditionary center of the Russian Defense Ministry and the Russian Geographical Society. ROTTERDAM, March 12 -- An unprotected database in China with the personal information of more than 1.8 million women — including their phone numbers, addresses and even a "BreedReady" status — has been uncovered by a Dutch cyber expert. The researcher with non-profit group GDI. foundation, found the insecure data detailing the women's identity numbers, education and marital status while searching for open databases in China over the weekend. He shared his findings in a series of partially redacted screenshots on Twitter in the hope of sourcing more information. "When we do, we will share this." He later told the Times the database was taken offline on Monday afternoon. It is still unclear what "BreedReady" actually means — some observers speculated it could be a poor English translation of women who are at a "child-bearing age", while others argued it meant women who "have children". According to the reseacher's findings, the youngest woman in the database was just 15 years old, while the oldest was 95. About 82 per cent of the women lived in Beijing. The database also showed that nearly 90 per cent of the women were single and their average age was 32. The discovery is timely in the context of Chinese government scholars' recent findings that the country is set to face a long period of "unstoppable" population decline after an expected peak of 1.44 billion people in 2029. While China abolished its controversial "one-child policy" aimed at curbing population growth in 2016 — allowing couples to have two children — the growth rate continued to slow in 2018. Numbers released by the National Bureau of Statistics in January showed new births in China fell to 15.23 million in 2018 — nearly 2 million fewer than 2017. 'This is horrifying'Chinese netizens were quick to draw comparisons between the database and the television show The Handmaid's Tale, based on a dystopian future where women are forced to reproduce to repopulate a world facing a plummeting birth rate. "It's just so weird … they even have ID numbers, phone numbers, home address and even indication of whether [they are] breed-ready. This is horrifying," wrote a Weibo user with the nickname Haidaidaiya. But other users on the social media platform took the opportunity to rebuke Western media for criticising China. "There are too many liars and some idiots really don't have enough wisdom — some western media are not dumb, but devious," another user with the nickname Lansedecaochong posted on Weibo.
TORONTO, March 11 -- Greenpeace co-founder and former president of Greenpeace Canada Patrick Moore described the cynical and corrupt machinations fueling the narrative of anthropocentric global warming and “climate change”.
In a Wednesday interview on SiriusXM’s Breitbart News Tonight with hosts Rebecca Mansour and Joel Pollak, Moore explained how fear and guilt are leveraged by proponents of climate change: Fear has been used all through history to gain control of people’s minds and wallets and all else, and the climate catastrophe is strictly a fear campaign — well, fear and guilt — you’re afraid you’re killing your children because you’re driving them in your SUV and emitting carbon dioxide into the atmosphere and you feel guilty for doing that. There’s no stronger motivation than those two. Scientists are co-opted and corrupted by politicians and bureaucracies invested in advancing the narrative of “climate change” in order to further centralize political power and control, explained Moore. Moore noted how “green” companies parasitize taxpayers via favorable regulations and subsidies ostensibly justified by the aforementioned narrative’s claimed threats, all while enjoying propagandistic protection across news media” And so you’ve got the green movement creating stories that instill fear in the public. You’ve got the media echo chamber — fake news — repeating it over and over and over again to everybody that they’re killing their children. And then you’ve got the green politicians who are buying scientists with government money to produce fear for them in the form of scientific-looking materials. And then you’ve got the green businesses, the rent-seekers, and the crony capitalists who are taking advantage of massive subsidies, huge tax write-offs, and government mandates requiring their technologies to make a fortune on this. And then, of course, you’ve got the scientists who are willingly, they’re basically hooked on government grants. When they talk about the 99 percent consensus among scientists on climate change, that’s a completely ridiculous and false number. But most of the scientists — put it in quotes, scientists — who are pushing this catastrophic theory are getting paid by public money, they are not being paid by General Electric or Dupont or 3M to do this research, where private companies expect to get something useful from their research that might produce a better product and make them a profit in the end because people want it — build a better mousetrap type of idea. But most of what these so-called scientists are doing is simply producing more fear so that politicians can use it to control people’s minds and get their votes because some of the people are convinced, ‘Oh, this politician can save my kid from certain doom.’ The narrative of anthropogenic global warming or “climate change” is an existential threat to reason, warned Moore: It is the biggest lie since people thought the Earth was at the center of the universe. This is Galileo-type stuff. If you remember, Galileo discovered that the sun was at the center of the solar system and the Earth revolved around it. He was sentenced to death by the Catholic Church, and only because he recanted was he allowed to live in house arrest for the rest of his life. So this was around the beginning of what we call the Enlightenment, when science became the way in which we gained knowledge instead of using superstition and instead of using invisible demons and whatever else, we started to understand that you have to have observation of actual events and then you have to repeat those observations over and over again, and that is basically the scientific method. “But this abomination that is occurring today in the climate issue is the biggest threat to the Enlightenment that has occurred since Galileo,” declared Moore. “Nothing else comes close to it. This is as bad a thing that has happened o science in the history of science.” Moore concluded, “It’s taking over science with superstition and a kind of toxic combination of religion and political ideology. There is no truth to this. It is a complete hoax and scam.” The first energy system they are building is a solid fuel molten salt reactor that achieves high temperatures to maximize efficiency of combined heat and power generation applications. However, to fully realize thorium's energy potential and in this way solve an important mission for China - the security of fuel supply - requires also the thorium itself to be fluid. This is optimized in the Thorium Molten Salt Reactor (TMSR). The TMSR takes safety to an entirely new level and can be made cheap and small since it operates at atmospheric pressure, one of its many advantages. Thanks to its flexible cooling options it can basically be used anywhere, be it a desert, a town or at sea. In China this is of special interest inland, where freshwater is scarce in large areas, providing a unique way to secure energy independence. History of the TMSR In the sixties, the TMSR was born in the secretive US Government research facility Oak Ridge National Laboratory (ORNL). There, the Molten Salt Reactor Experiment (MSRE) ran successfully for more than 4 years and demonstrated its feasibility and stable nature. In the seventies, the Shanghai Institute of Applied Physics, under conditions of a short deadline, constructed a cold test of a molten salt reactor. Since we entered the 21st century, TMSRs have received global attention. The U.S., the European Union, Russia, and Japan have all developed conceptual designs, investigated related technologies and begun practical experiments. In 2011, the Chinese Academy of Sciences commenced the "Near future disruptive change in atomic energy - Thorium Molten Salt Reactor apparatus", a strategic science and technology pilot project with political power behind. As a result, TMSR research, the practical realization of thorium's high fuel efficiency and high temperature utility began in experiments. During the past 5 years, the development of key systems and technologies have made vital advancements such as the specialized development of the simulation and modeling system. With this system, the world's first experimental solid fuel molten salt reactor engineering design has been completed. With national and international co-operation, a safety standard for thorium molten salt reactors has been formulated as well as documentation regarding anti-proliferation and safety classification. Specific breakthroughs have occurred in the molten salt reactor itself as well as techniques related to many crucial areas in the molten salt reactor: loop testing has been successfully researched, and molten salt pumps have been developed along with molten salt heat exchanges, high-temperature instrumentation and controls. The Devil is in the Details
China has built the world's first industrial scale high temperature experimental fluoride salt loop as well as the world's largest passive natural circulation loop for molten salts. Large scale experimental facilities have been constructed to advance the closed thorium-uranium fuel cycle through reprocessing strategies. The minor actinides created can be used as fuel and the extra U-233 bred can be used to start new reactors, enabling China to finally reach the goal of a fully closed nuclear fuel cycle. Since the Chinese TMSR uses all the thorium, only fission products will be sent to geological disposition, reducing the quantity and longevity of the fission products by orders of magnitude. Further, realising the high-temperature Brayton cycle turbine technology for power generation can significantly increase the heat to electricity conversion and reduce the need for cooling water. China has also solved the molten salt permeation problem and the difficult question of graphite swelling. A special project has developed a world-first high density, fine-grain graphite - and has developed the means of industrial production of it. They have also developed a specialized nickel alloy, secured its production and handling in China, as well as solved the difficult problem of fluoride salt corrosion control. Pioneering A New Era Powered by Thorium Since the start, the TMSR project has grown to a professional research team of over 400 researchers. Significant progress has been made in relevant fields of design and construction, advanced thorium molten salt reactor platforms have been constructed, and conditions necessary for experiments have been created. TMSR energy systems have obtained widespread and close attention from both research institutions within China and the growing international community. “Everyone in the field is extremely impressed with how China saw the potential, grabbed the opportunity and is now running faster than everyone else developing this futuristic energy source China and the entire world is in a great need of.” The potential of this development has fueled discussions among international experts. As China ushers in the time of the Thirteenth Five-Year-Plan, there is trust in Thorium Energy to become the backbone of the nation's research efforts, and to advance China as a nuclear energy country and greatly contribute to becoming a nuclear energy powerhouse. SILICON VALLEY, March 4 -- The world is literally a greener place than it was 20 years ago, and data from NASA satellites has revealed a counterintuitive source for much of this new foliage: China and India. A new study shows that the two emerging countries with the world’s biggest populations are leading the increase in greening on land. The effect stems mainly from ambitious tree planting programs in China and intensive agriculture in both countries. The greening phenomenon was first detected using satellite data in the mid-1990s by Ranga Myneni of Boston University and colleagues, but they did not know whether human activity was one of its chief, direct causes. This new insight was made possible by a nearly 20-year-long data record from a NASA instrument orbiting the Earth on two satellites. It’s called the Moderate Resolution Imaging Spectroradiometer, or MODIS, and its high-resolution data provides very accurate information, helping researchers work out details of what’s happening with Earth’s vegetation, down to the level of 500 meters, or about 1,600 feet, on the ground. Taken all together, the greening of the planet over the last two decades represents an increase in leaf area on plants and trees equivalent to the area covered by all the Amazon rainforests. There are now more than two million square miles of extra green leaf area per year, compared to the early 2000s – a 5% increase. “China and India account for one-third of the greening, but contain only 9% of the planet’s land area covered in vegetation – a surprising finding, considering the general notion of land degradation in populous countries from overexploitation,” said Chi Chen of the Department of Earth and Environment at Boston University, in Massachusetts, and lead author of the study. An advantage of the MODIS satellite sensor is the intensive coverage it provides, both in space and time: MODIS has captured as many as four shots of every place on Earth, every day for the last 20 years. “This long-term data lets us dig deeper,” said Rama Nemani, a research scientist at NASA’s Ames Research Center, in California’s Silicon Valley, and a co-author of the new work. “When the greening of the Earth was first observed, we thought it was due to a warmer, wetter climate and fertilization from the added carbon dioxide in the atmosphere, leading to more leaf growth in northern forests, for instance. Now, with the MODIS data that lets us understand the phenomenon at really small scales, we see that humans are also contributing.”
China’s outsized contribution to the global greening trend comes in large part (42%) from programs to conserve and expand forests. These were developed in an effort to reduce the effects of soil erosion, air pollution and climate change. Another 32% there – and 82% of the greening seen in India – comes from intensive cultivation of food crops. Land area used to grow crops is comparable in China and India – more than 770,000 square miles – and has not changed much since the early 2000s. Yet these regions have greatly increased both their annual total green leaf area and their food production. This was achieved through multiple cropping practices, where a field is replanted to produce another harvest several times a year. Production of grains, vegetables, fruits and more have increased by about 35-40% since 2000 to feed their large populations. How the greening trend may change in the future depends on numerous factors, both on a global scale and the local human level. For example, increased food production in India is facilitated by groundwater irrigation. If the groundwater is depleted, this trend may change. “But, now that we know direct human influence is a key driver of the greening Earth, we need to factor this into our climate models,” Nemani said. “This will help scientists make better predictions about the behavior of different Earth systems, which will help countries make better decisions about how and when to take action.” The researchers point out that the gain in greenness seen around the world and dominated by India and China does not offset the damage from loss of natural vegetation in tropical regions, such as Brazil and Indonesia. The consequences for sustainability and biodiversity in those ecosystems remain. Overall, Nemani sees a positive message in the new findings. “Once people realize there’s a problem, they tend to fix it,” he said. “In the 70s and 80s in India and China, the situation around vegetation loss wasn’t good; in the 90s, people realized it; and today things have improved. Humans are incredibly resilient. That’s what we see in the satellite data.” CAPE CANAVERAL, March 3 -- SpaceX’s new crew capsule arrived at the International Space Station on Sunday, acing its second milestone in just over a day. No one was aboard the Dragon capsule launched Saturday on its first test flight, only an instrumented dummy. But the three station astronauts had front-row seats as the sleek, white vessel neatly docked and became the first American-made, designed-for-crew spacecraft to pull up in eight years. TV cameras on Dragon as well as the space station provided stunning views of one another throughout the rendezvous. If the six-day demo goes well, SpaceX could launch two astronauts this summer under NASA’s commercial crew program. Both astronauts — Doug Hurley and Bob Behnken — were at SpaceX Mission Control in Southern California, observing all the action. They rushed there from Florida after watching the Dragon rocket into orbit early Saturday from NASA’s Kennedy Space Center. “Just super excited to see it,” Behnken said minutes after the link-up. “Just one more milestone that gets us ready for our flight coming up here.” While SpaceX has sent plenty of cargo Dragons to the space station, crew Dragon is a different beast. It docked autonomously under the station astronauts’ watchful eyes, instead of relying on the station’s robot arm for berthing. Behnken said that’s the way it should work when he and Hurley are on board; they may push a button or two and will have the ability to intervene, if necessary. As part of Sunday’s shakedown, the station astronauts sent commands for the Dragon to retreat and then move forward again, before the capsule closed in for good. SpaceX employees at company headquarters in Hawthorne, California, cheered and applauded as crew Dragon pulled up and docked at the orbiting lab, nearly 260 miles (400 kilometers) above the Pacific, north of New Zealand. They burst into applause again, several minutes later, when the Dragon’s latches were tightly secured. The station astronauts offered congratulations to SpaceX, as they got ready to open the hatches and collect the supplies stashed aboard Dragon. The capsule’s lone passenger — a mannequin wearing a white SpaceX spacesuit — also was going to be welcomed aboard. The test dummy — or Smarty as SpaceX likes to call it, given all the instrumentation — is named Ripley after the lead character in the science-fiction “Alien” films. Dragon will remain at the space station until Friday, when it undocks and aims for a splashdown in the Atlantic, a couple hundred miles off the Florida coast. Like Ripley, the capsule is rigged with sensors to measure noise, vibration and stresses, and to monitor the life-support, propulsion and other critical systems throughout the flight. SpaceX aims to launch Behnken and Hurley as early as July Next up, though, should be Boeing, NASA’s other commercial crew provider. Boeing is looking to launch its Starliner capsule without a crew as early as April and with a crew possibly in August. NASA is paying the two private companies $8 billion to build and operate the capsules for ferrying astronauts to and from the space station. Astronauts have been stuck riding Russian rockets ever since NASA’s space shuttle program ended in 2011. Russian Soyuz seats go for up to $82 million apiece. ROTTERDAM, March 2 -- Besides gaseous pollutants, the atmosphere can also be polluted by particles. These particles (either in suspension, fluid or in solid state), have a divergent composition and size and are sometimes called aerosols. They are often catalogued as 'floating dust', but are best known as particulate matter (PM). This floating dust is most often categorized based on their aerodynamic diameter. The aerodynamic diameter of a dust particle is the diameter of a sphere-shaped particle that shows the same behavior in the atmosphere as a dust particle (which does not necessarily have a sphere shape). In the framework of air quality problems, particulate matter is the most important. Particulate matter such as PM10, PM2.5, PM1 and PM0.1 is defined as the fraction of particles with an aerodynamic diameter smaller than respectively 10, 2.5, 1 and 0.1 µm (for your information: 1 µm = 1 millionth of a meter or 1 thousandth of a millimeter). In comparison, the average diameter of a human hair equals 50-70 µm (see figure below) Bigger particles, after being emitted into the atmosphere, quickly get taken down by gravity or are washed out by rain. The finer particles can remain in the atmosphere for a longer time (a couple of days to weeks). As such, these finer particles can be transported over longer distances. Another consequence of this longer stay in the atmosphere is the possible alteration of composition and the change of characteristics of the particles because of physicochemical processes.
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