Time filter

Source Type

Saint-Sauveur-en-Rue, France

Crawled News Article
Site: http://phys.org/space-news/

Colorado State University researchers are creating the next generation of such monitoring satellites. They are doing it at a hundredth the size and weight scale, though, by using not just one, but a constellation of satellites. Supported by an $8.2 million NASA award managed by the Earth Science Technology Office, a team led by Steven Reising, professor of electrical and computer engineering, is developing instrumentation for satellites about the size of a hardback dictionary, called CubeSats, that can observe, in real time, a storm as it grows and progresses. They will demonstrate their technology aboard a launch awarded by NASA earlier this year. Their project is called the Temporal Experiment of Storms and Tropical Systems - Demonstrator, or TEMPEST-D. TEMPEST-D will demonstrate the ability to monitor the atmosphere with small satellites. The team will demonstrate a radiometer aboard a 6U CubeSat (30 cm by 20 cm by 10 cm, or about 12 inches by 8 inches by 4 inches), and subsequently plan to deploy a constellation of satellites to study cloud processes. V. "Chandra" Chandrasekar, professor of electrical and computer engineering, a co-investigator on the program, also works on the Global Precipitation Mission (GPM), an international network of satellites providing the state of the art in rainfall and snow monitoring. Reising, Chandra, and co-investigator Christian Kummerow, professor of atmospheric science and director of CSU's Cooperative Institute for Research on the Atmosphere (CIRA), are working to demonstrate the utility of a single CubeSat now, then a constellation of them later, to conduct systematic and routine measurements over the globe. Their long-term plan is to deploy a constellation of CubeSats that can perform rapid overpasses of developing storms, taking thousands of images inside clouds. The TEMPEST-D team includes key partners at NASA/Caltech's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. The JPL effort is led by Project Manager Todd Gaier. "We are trying to improve our understanding of the processes in storms leading to rain, snow and other precipitation," Chandra said. The biggest technical challenge? Squeezing many of the capabilities of a large satellite into one that weighs just 8 kilograms (17.6 lbs.). Reising's team has spent over a decade working to miniaturize a microwave radiometer to fit inside a CubeSat. "We will be able to observe storms in ways not yet possible with the current fleet of satellites in orbit," Reising said. Explore further: Measuring ice particles and water vapor in the upper troposphere

Scigliano R.,CIRA | Gardi R.,CIRA | Del Vecchio A.,CIRA
Proceedings of the International Astronautical Congress, IAC

The purpose of this paper is to present on one hand the applicability of fiber-reinforced Ultra High Temperature Ceramics (UHTC) and UHTC coated metals to space missions and on the other hand the plasma sprayed ceramic coating technique on refractory metals for space applications. CIRA has designed two UHTC winglets to be installed on the Australian rocket SCRAMSPACE. The paper describes the new material selected for this experiment, a fiber reinforced UHTC, and a new technology of UHTC coating. The present paper presents also, an application of ceramic coatings technique in the field of aerospace hypersonic vehicles, where the high thermal loads are coupled with highly reactive plasma environment. The results of a material selection campaign conducted by CSM and CIRA is presented. A set of substrates, coatings and deposition techniques have been individuated as possible candidates for a real flight test. Many samples have been realized and tested. A first selection was based on pull test, the final selection was accomplished by means of plasma torch test, exposing conical samples to very high temperatures. The result is at the selection of a substrate/coating system that shall be used in future real flight applications. Copyright ©2014 by the International Astronautical Federation. All rights reserved. Source

Crawled News Article
Site: http://motherboard.vice.com/

If you’ve ever read your internet connection’s fine print, you’ve probably seen a disclaimer about speeds. Take, for example, my ISP, a local Canadian provider called TekSavvy. They’re usually pretty fast, and I’ve never had reason to complain, but nevertheless, they offer this disclaimer: “Speed is a function of many technical factors, some of which are not under our control. As such, we do not guarantee the maximum Service performance (i.e., throughput or speed) levels.” Ideally, this language should merely serve to cover an ISP’s ass for when occasional hiccups occur. But what happens when you never get speeds approaching what’s promised? What recourse do you have? In an attempt to figure out what level of service Canadian internet subscribers are really getting across the country, the Canadian Radio-television Telecommunications Commission (CRTC) announced on Wednesday that it is preparing to release the country’s first national independent broadband performance report this Spring. The initiative was first announced in May with a call for volunteers. Nearly 28,000 Canadians have since signed up to install devices in their homes designed to test the performance of broadband internet connections. The CRTC ultimately selected 4,500 participants from a wide range of ISPs—including major players such as Rogers, Vidéotron, TELUS, and Bell—as well as different tiers of internet service, “covering a variety of their most popular Internet speeds.” Read More: How First Nations Kids Built Their Own Internet Infrastructure The devices are being provided by a UK-based company, SamKnows, and “testing is only being undertaken when users are not actively using their Internet connection,” according to the CRTC. “No information concerning online activities is being collected to protect subscriber privacy.” The report is part of a larger initiative launched by the CRTC in April of this year, designed to review the level of basic telecommunications services available to Canadians, and reexamine baseline internet connection speed targets previously established by the CRTC. By the end of the year, the CRTC expects all Canadians to have access to broadband internet speeds of at least 5 Mbps for downloads and 1 Mbps for uploads—a target that was set in 2011. By comparison, the broadband speed target in the US was increased to 25 Mbps for downloads and 3 Mbps for uploads at the beginning of 2015. Organizations such as Netflix have performed limited tests of ISPs in Canada in the past—the streaming video service ranks providers based on Netflix performance during prime-time hours—and the Canadian Internet Registration Authority (CIRA) announced a web-based performance testing service earlier this year. But by installing dedicated testing hardware on-site in users’ homes, the CRTC report should hopefully give the most complete and comprehensive report of Canadian internet connection quality and speeds we’ve had to date.

Crawled News Article
Site: http://news.mit.edu/topic/mitenvironment-rss.xml

Reducing global greenhouse gas emissions could have big benefits in the U.S., according to a report released today by the U.S. Environmental Protection Agency (EPA), including thousands of avoided deaths from extreme heat, billions of dollars in saved infrastructure expenses, and prevented destruction of natural resources and ecosystems. The report, “Climate Change in the United States: Benefits of Global Action,” relies on research developed at the MIT Joint Program on the Science and Policy of Global Change to estimate the effects of climate change on 22 sectors in six areas: health, infrastructure, electricity, water resources, agriculture and forestry, and ecosystems. The report compares two possible futures: one with significant global action on climate change, and one in which greenhouse gases continue to rise. “Understanding the risks posted by future climate change informs policy decisions designed to address those risks,” says John Reilly, co-director of the MIT Joint Program on the Science and Policy of Global Change. “This report quantifies the risks we might face by taking no action.” The MIT researchers developed two suites of future climate scenarios, socioeconomic scenarios, and technological assumptions that serve as the foundation of the EPA report’s findings. In the first scenario, no new constraints were placed on greenhouse gas emissions. In the second, global warming was limited to 2 degrees Celsius through global climate action. Research groups across the country then built on the scenarios developed at MIT to study how different sectors in the U.S. would fare under each future scenarios. The groups studied a diverse range of impacts of climate change according to their own areas of expertise, ranging from lost wages due to extreme temperatures, to damage to bridges from heavy river flows, to destruction of Hawaii’s coral reefs, among others. The MIT team also contributed heavily to the section of the report focusing on water resources. The report concludes that mitigating greenhouse gas emissions can reduce the risk of both damaging floods and droughts, and prevent future water management issues. “Water is fundamentally linked to climate.” Reilly says. “Water needs to be in the right place at the right time. So as temperatures rise and precipitation patterns shift, you run the risk of having a mismatch between demand for water and the available supply in an area.” The report is part of the ongoing Climate Impacts and Risk Analysis (CIRA) program, an EPA-led collaborative modeling effort among teams in the federal government, MIT, the Pacific Northwest National Laboratory, the National Renewable Energy Laboratory, and several consulting firms. The scenarios developed at MIT serve as a common tie between the results produced by the many teams participating in the project. Each team used the MIT scenarios as inputs to their own modeling tools, uniting all of the estimates in the report with a set of shared assumptions about emissions growth and possible changes in future climate. The report summarizes more than 35 studies that were individually peer reviewed in scientific journals. The full report and related materials are available at epa.gov/cira.

Crawled News Article
Site: http://news.mit.edu/topic/mitenvironment-rss.xml

Since the 1990s, scientists and policymakers have proposed limiting Earth’s average global surface temperature to 2 degrees Celsius above pre-industrial levels, thereby averting the most serious effects of global warming, such as severe droughts and coastal flooding. But until recently, they lacked a comprehensive estimate of the likely social and economic benefits — from lives saved to economies preserved — that would result from greenhouse gas emissions reduction policies designed to achieve the 2-degree goal. Now, a team of researchers from the MIT Joint Program on the Science and Policy of Global Change has published a study in Climatic Change that provides scenarios that climate scientists can use to estimate such benefits. The study projects greenhouse gas emissions levels and changes in precipitation, ocean acidity, sea level rise and other climate impacts throughout the 21st century resulting from different global greenhouse gas (GHG) mitigation scenarios. The scenarios include a business-as-usual future and one aimed at achieving significant GHG emission reductions limiting global warming since pre-industrial times to 2 C. Research groups convened by the U.S. Environmental Protection Agency have already begun using the MIT projections to evaluate the benefits of a 2 C emissions reduction scenario for agriculture, water, health, and other global concerns. “The U.S. EPA used our scenarios for a report on the benefits of global climate action, which, to my knowledge, is the most comprehensive analysis to date to quantify the economic, health, and environmental benefits for the United States from greenhouse gas emission mitigation,” says Sergey Paltsev, co-author of the Climatic Change study and a senior research scientist and deputy director at the MIT Joint Program. “We have much more experience defining the cost of mitigation than the benefits. The goal of this project was to put a dollar value on damages from climate change in a number of sectors.” Putting a dollar value on the benefits of climate action Using its Integrated Global System Model (IGSM) — which tracks climate, socioeconomic, and technological change over time — to produce its greenhouse gas emissions and climate change projections, the MIT team ran global policy scenarios through simulations designed to capture a range of uncertainty in the climate’s response to changes in average global temperature. According to the team’s estimates, with no policy implemented between now and 2100, increases in global temperature will range from 3.5 to 8 degrees C, precipitation from 0.3 to 0.6 millimeters per day and sea level from 40 to 80 centimeters. Ocean acidity will also rise, threatening marine life and commercial fisheries. Global GHG emissions reduction policies, which lower greenhouse gas concentrations, would reduce these climate impacts considerably. Based on the MIT projections, the EPA report, “Climate Change in the United States: Benefits of Global Action,” shows that a 2 C stabilization would save thousands of lives threatened by extreme heat and billions of dollars in infrastructure expenses, while preventing destruction of natural resources and ecosystems. Prepared as part of the ongoing Climate Change Impacts and Risk Analysis (CIRA) project, an EPA-led collaborative modeling effort among teams in the federal government, MIT, the Pacific Northwest National Laboratory, the National Renewable Energy Laboratory and several consulting firms, the report estimates how climate change would impact 20 sectors in health, infrastructure, electricity, water resources, ecosystems and agriculture and forestry. In more than 35 studies, the EPA-funded researchers pinpointed a large number of climate impacts that could be averted, or at least reduced, by a 2 C stabilization, from lost wages due to extreme temperatures, to damage to bridges from heavy river flows. By enabling scientists to calculate damages incurred under different global mitigation scenarios on each impact sector, the IGSM-based projections are empowering them to put a dollar value on the benefits of more aggressive climate action. The MIT study found that the intended effects of more stringent climate policy would not be realized until the second half of the century, when they would begin to outweigh the effects of natural climate variability. By the end of the century, however, climate policies would result in significantly lower temperatures, greenhouse gas emissions and climate impacts than the no-policy option. “Even in aggressive emissions reduction scenarios we don’t see a response in climate and temperature until mid-century, but by 2100 the response is dramatic,” Paltsev says. “It’s hard to achieve global consensus on such policies because the costs must be paid now and the benefits come later.” But this CIRA project, which only captures some of the impacts of climate change, demonstrates that the benefits to the U.S. of global climate action can be substantial, and that they grow over time. Paltsev cautions that by delaying action until more negative effects of climate change are felt, the world will have fewer options at its disposal to stabilize the global climate. This research was partially funded by the EPA; the IGSM is supported by a consortium of government, industry, and foundation sponsors of the MIT Joint Program.

Discover hidden collaborations