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<span style="background-color:white;"><strong><font face="Arial,sans-serif"><br /><font size="4"><span style="color:#fe2419;">[速度2-9]<br /></span><br />Clammy Change<br /></font></font>Clammy Change<br /></strong></span><br /><span style="background-color:white;"><font size="3"><font face="Arial,sans-serif">Will global warming make the planet more humid, too?<br /></font></font></span><br /><span style="background-color:white;"><em><span style="color:#660033;"><font size="2"><font face="Georgia,serif">By Brian Palmer</font></font></span></em><em><span style="color:#660033;"><font size="2"><font face="Georgia,serif"></font></font></span></em><span style="color:#666666;"><font size="2"><font face="Arial,sans-serif"> osted Tuesday, July 12, 2011, at 6:01 PM ET</font></font></span><span style="color:#666666;"><font size="2"><font face="Arial,sans-serif"><br /></font></font></span></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><br /><span style="background-color:white;"><span style="color:#f10b00;"><font size="2"><font face="SimSun">计时</font></font><font size="2"><font face="Verdana,sans-serif">1</font></font><font size="2"><font face="SimSun">(</font></font><font size="2"><font face="Verdana,sans-serif">235 words</font></font><font size="2"><font face="SimSun">)</font></font><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span></span><br /><span style="background-color:white;"><a href="http://mediagallery.usatoday.com/Heat+wave+broils+Midwest+and+Southern+states/G2479" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">Hot, muggy weather</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> created dangerous conditions for residents of the South and Midwest on Tuesday, and there were </font></font><a href="http://www.kansascity.com/2011/07/11/3007377/two-more-possible-heat-deaths.html" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">reports</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> of </font></font><a href="http://www.stltoday.com/news/local/illinois/article_d70e5182-abb8-11e0-903c-001a4bcf6878.html" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">heat-related deaths</font></font></span></a><font size="2"><font face="Verdana,sans-serif">. We all know that it's impossible to link any particular heat wave to the phenomenon of global warming, but those of us suffering in humid areas have to be wondering—is the Earth getting wetter, too?<br /></font></font></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif">Most climatologists think so. The planet's total humidity seems likely to rise in the coming years. But there's a difference between that figure—which represents the mass of all the water vapor in the air—and the planet's relative humidity, which describes how close the air is, on average, to its saturation point at a given temperature. Total humidity is the more important metric for the planet, because water vapor is itself a greenhouse gas. Relative humidity, on the other hand, is more closely associated with human comfort, because it affects your ability to cool off by sweating. Few scientists profess to know with certainty what's going to happen to either measure over the next few decades or centuries. There's </font></font><a href="http://www.cru.uea.ac.uk/cru/pubs/thesis/2007-willett/1INTRO.pdf" target="_blank"><span style="color:#800080;"><font size="2"><font face="Verdana,sans-serif">very little global data</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> (PDF) on the issue, and those that do exist are in dispute. The majority view appears to be that relative humidity will remain more or less stable,and most climate change models are based on this assumption. If relative humidity holds constant while the temperature rises, there will be an increase in absolute humidity. <br /></font></font></span><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><br /><span style="background-color:white;"><span style="color:#f10b00;"><font size="2"><font face="SimSun">计时</font></font><font size="2"><font face="Verdana,sans-serif">2 (235 words)<br /></font></font></span></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif">In recent years, a few well-known scientists have rejected the assumption of stable relative humidity, however, and we're now in the middle of a dust-up in the field. On one side, there is evidence that relative humidity can </font></font><a href="http://www.eike-klima-energie.eu/uploads/media/Paltridge_01.pdf" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">change significantly</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> (PDF) over time, particularly at higher altitudes. There's even some indication that it has </font></font><a href="http://wattsupwiththat.com/2009/03/05/negative-feedback-in-climate-empirical-or-emotional/" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">declined</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> over the last half-century. On the other, scientists point to data that absolute humidity at ground level </font></font><a href="http://www.cru.uea.ac.uk/cru/pubs/thesis/2007-willett/6INTRO.pdf" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">rose by about 2.2 percent</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> (PDF) overall between 1973 and 2003. The increases were particularly significant in the tropics and the northern hemisphere. (Some parts of the globe </font></font><a href="http://www.metoffice.gov.uk/hadobs/hadcruh/" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">dried out</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> over that period, too.)<br /></font></font></span><span style="background-color:white;"><span style="color:#999999;"><font face="Verdana,sans-serif"><br /></font></span><font size="2"><font face="Verdana,sans-serif">It's possible for both sides to be correct. If relative humidity declines modestly, significant increases in temperature would still lead to a rise in absolute humidity.<br /></font></font></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif">This isn't just a dispute over how sweaty your grandchildren are going to be. Absolute humidity levels have a powerful effect on temperature projections. If scientists are wrong about humidity, they could have the temperature projections wrong as well. Water vapor can create a feedback loop that accelerates the effects of other greenhouse gases like carbon dioxide and methane. As the climate warms, the air soaks up more moisture. The moisture then prevents heat from radiating through the atmosphere and into space, which warms the air further, enabling it to hold still more water. Most climate change models take this cycle into account.</font></font><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><br /><span style="background-color:white;"><strong><font face="Arial,sans-serif">How Does the Heat Index Work?<br /></font></strong></span><br /><span style="background-color:white;"><font size="3"><font face="Arial,sans-serif"> retty well, if you're 5-feet-7.<br /></font></font></span><br /><span style="background-color:white;"><em><span style="color:#660033;"><font size="2"><font face="Georgia,serif">By Daniel Engber</font></font></span></em><em><span style="color:#660033;"><font size="2"><font face="SimSun"></font></font></span></em><span style="color:#666666;"><font size="2"><font face="Arial,sans-serif"> osted Wednesday, July 27, 2005, at 6:39 PM ET</font></font></span><span style="color:#666666;"><font size="2"><font face="Arial,sans-serif"><br /></font></font></span></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif"><span style="color:#f10b00;"></span><br /></font></font></span><br /><span style="background-color:white;"><span style="color:#f10b00;"><font size="2"><font face="SimSun">计时</font></font><font size="2"><font face="Verdana,sans-serif">3 (245 words)<br /></font></font></span></span><br /><span style="background-color:white;"><em><font size="2"><font face="Verdana,sans-serif">Hot, humid air led to heat-index readings of 100 and above across </font></font></em><a href="http://www.nj.com/weather-guy/index.ssf/2011/06/newark_breaks_record_heat_inde.html" target="_blank"><em><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">many</font></font></span></em></a><em><font size="2"><font face="Verdana,sans-serif"></font></font></em><a href="http://www.reuters.com/article/2011/06/08/us-weather-heat-idUSTRE75765220110608" target="_blank"><em><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">parts</font></font></span></em></a><em><font size="2"><font face="Verdana,sans-serif"> of the country last week. What exactly is the heat index, and how does it work? Daniel Engber's 2005 "Explainer" on the topic is reprinted below.</font></font></em><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif"><br />Feelin' hot, hot, hot!</font></font><font size="2"><font face="Verdana,sans-serif">A national heat wave is expected to reach its </font></font><a href="http://www.usatoday.com/weather/climate/2005-07-26-heat-usat_x.htm?POE=NEWISVA" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">peak</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> today, as temperatures along the East Coast rise into the 90s and 100s. To make things worse, the high humidity has produced </font></font><a href="http://www.decaturdaily.com/decaturdaily/news/050722/hot.shtml" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">heat</font></font></span></a><font size="2"><font face="Verdana,sans-serif"></font></font><a href="http://www.zwire.com/site/news.cfm?newsid=14920250&BRD=1697& AG=461&dept_id=44551&rfi=6" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">indexes</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> of between 110 and 120. What's the "heat index," and how does it work?<br /></font></font><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif"><br /></font></font><font size="2"><font face="Verdana,sans-serif">The heat index tells you how hot it feels at a given humidity. Moist air feels hotter than dry air because it makes sweating less efficient. On a hot, dry day, your sweat will evaporate quickly and cool your skin; under humid conditions, sweat evaporates more slowly and doesn't do as much. Just as the </font></font><a href="http://www.msc.ec.gc.ca/education/windchill/science_equations_e.cfm" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">wind chill</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> attempts to measure how cold it feels under certain wind conditions, the heat index tries to measure how hot it feels given the humidity.<br /></font></font></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif">The formula for heat index is based on work completed in the late 1970s. R. G. Steadman wrote a paper called "The assessment of sultriness," in which he used a list of </font></font><a href="http://64.233.161.104/search?q=cache:e-wtKhBhdn8J:www.srh.noaa.gov/ffc/html/studies/ta_htindx.PDF+&hl=en&client=firefox-a" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">20 factors</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> to compute how hot you might feel on a given day. These factors included the rate at which you sweat, the type of clothes you're wearing, the surface area of your body, and what you happen to be doing. </font></font><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><span style="background-color:white;"><span style="color:#f10b00;"><font size="2"><font face="SimSun">计时</font></font><font size="2"><font face="Verdana,sans-serif">4 (288 words)<br /></font></font></span></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif">To isolate the effects of temperature and humidity on the perception of heat, Steadman invented a typical situation: A person who's 5 feet 7 inches and weighs 147 pounds walks at about 3.1 miles per hour in a light breeze, wearing long pants and a short-sleeved shirt. Then Steadman filled out his 20 variables with information from this scenario and figured out how hot his fictional person would feel at different outside temperatures and levels of humidity. He put the results in a table: Higher humidity would make his exemplar feel hotter, while drier conditions would make him feel cooler than it really is. For any given temperature, there is a percent humidity at which the weather "feels" exactly as hot as the thermometer indicates.<br /></font></font></span><br /><div style="text-align:center;"><div style="text-align:center;"><span style="background-color:white;"><em><span style="color:#666666;"><font size="2"><font face="Verdana,sans-serif"></font></font></span></em></span></div><br /><br /></div><br /><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif">Meteorologists with the National Weather Service used Steadman's table to derive a simpler </font></font><a href="http://www.srh.noaa.gov/bmx/tables/hindex.html" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">formula</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> for heat index by creating a function that approximates its values (to within 1.3 degrees Fahrenheit) using only two variables—temperature and percent humidity. Since the formula incorporates all of Steadman's assumptions, how hot you feel may differ from the heat index reported on the evening news. For example, weather reports say that today's heat index in </font></font><a href="http://www.weather.com/weather/local/10025?from=hrly_topnav_undeclared" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">New York City</font></font></span></a><font size="2"><font face="Verdana,sans-serif"> is 106, and that the wind is blowing at 11 miles per hour. But the formula for heat index assumes that the wind is blowing at only 5.8 miles per hour—so the added breeze might make it feel cooler than what's been reported. (Unless it were really hot out—when it gets up into the high 90s, the wind </font></font><a href="http://www.zunis.org/at_least_theres_a_breeze.htm" target="_blank"><span style="color:#0066cc;"><font size="2"><font face="Verdana,sans-serif">actually makes you hotter</font></font></span></a><font size="2"><font face="Verdana,sans-serif">.) Likewise, the further your dimensions are from 5 feet 7 inches and 147 pounds, the less likely you are to feel like it's 106 degrees.<br /></font></font></span><br /><span style="background-color:white;"><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><br /><strong><a href="http://www.wired.com/reviews/2011/06/mizuno-wave-prophecy/%20" target="_blank"><span style="color:#000000;"><font size="5"><font face="Arial">Mizuno’s Foamless Running Shoes Stiffen Your Step</font></font></span></a><span style="color:#000000;"><br /></span></strong><ul><font size="3"><font face="Calibri">Mizuno USA Wave Prophecy</font></font><br /><a href="http://www.wired.com/reviews/category/sports-and-outdoors/" target="_blank"><font size="3"><font face="Calibri">Sports and Outdoors</font></font></a><br /><font size="3"><font face="Calibri">· $200 </font></font><br /><font size="3"><font face="Calibri">· </font></font><a href="http://www.mizunousa.com/" target="_blank"><span style="color:#0000ff;"><font size="3"><font face="Calibri">Mizuno USA</font></font></span></a><br /></ul><font size="3"><font face="Calibri">Reviewed by </font></font><a href="http://www.wired.com/reviews/author/bbrown028/" target="_blank"><span style="color:#0000ff;"><font size="3"><font face="Calibri">Billy Brown</font></font></span></a><font size="3"><font face="Calibri">  June 29, 2011 </font></font><br /><font size="3"><font face="Calibri"></font></font><br /><br /><span style="background-color:white;"><span style="color:#f10b00;"><font size="2"><font face="SimSun">计时</font></font><font size="2"><font face="Verdana,sans-serif">5 (295 words)<br /></font></font></span></span><br /><font size="2"><font face="Verdana,sans-serif">While most shoe companies are chasing the minimalist craze and </font></font><a href="http://www.wired.com/reviews/2011/04/minimal-shoes/?pid=870&viewall=true" target="_blank"><font size="2"><font face="Verdana,sans-serif"><span style="color:#0000ff;">removing the bottoms</span></font></font></a><font size="2"><font face="Verdana,sans-serif"> of their shoes, Mizuno is going against the trend by doing away with the middle.<br /></font></font><br /><font size="2"><font face="Verdana,sans-serif">There’s a big hole right where the cushioning should be on </font></font><a href="http://www.mizunousa.com/running/feature/mizuno-wave-prophecy-running-shoes" target="_blank"><font size="2"><font face="Verdana,sans-serif"><span style="color:#0000ff;">Mizuno’s Wave Prophecy</span></font></font></a><font size="2"><font face="Verdana,sans-serif"> road shoe. In lieu of the usual </font></font><a href="http://en.wikipedia.org/wiki/Ethylene-vinyl_acetate" target="_blank"><font size="2"><font face="Verdana,sans-serif"><span style="color:#0000ff;">EVA foam</span></font></font></a><font size="2"><font face="Verdana,sans-serif"> midsole — usually the first part of running shoes to break down — Mizuno has substituted the Wave Infinity Plate, a system of the company’s own design that consists of two </font></font><a href="http://en.wikipedia.org/wiki/Thermoplastic_polyurethane" target="_blank"><font size="2"><font face="Verdana,sans-serif"><span style="color:#0000ff;">TPU</span></font></font></a><font size="2"><font face="Verdana,sans-serif"> plates connected at ten points along the shoe by rubber baffles. In addition to potentially lasting longer than traditional soles, the plate is meant to provide better cushioning and a more responsive stride for a variety of different running styles. And for $200 a pair, these shoes had certainly better knock one’s socks off.<br /></font></font><br /><font size="2"><font face="Verdana,sans-serif">I wasn’t convinced at first. Initially, the shoe’s firm ride was a little off-putting. But it wasn’t long before I started appreciating the tough love. The foamless sole acts kind of like a leaf spring, compressing with the impact of each strike, and it adapted to a variety of strikes. I felt supported and cushioned whether I ran with my usual forefoot strike or the plodding heelstrike that I devolve into after mile ten or so. But I was able to pull double-digit miles without feeling like my feet were getting beaten up.<br /></font></font><br /><font size="2"><font face="Verdana,sans-serif">I felt quicker in the shoes, too. On the toe-off end of the footstrike, the plate bends to about 15 degrees, then becomes rigid and snaps back just in time to add a bit of “oomph” to every step. During my runs, this helped me maintain a high turnover rate, making the shoe feel a lot lighter than the 15 ounces my size 11s weigh in at.</font></font><font size="2"><font face="Verdana,sans-serif"><br /></font></font><br /><span style="color:#f10b00;"><font size="2"><font face="SimSun">自由阅读</font></font><font size="2"><font face="Verdana,sans-serif"><br /></font></font></span><br /><font size="2"><font face="Verdana,sans-serif">With all the craziness going on under the foot, it can be easy to overlook the Wave Prophecy’s upper. The main component is a stretchy, mesh fabric — Mizuno calls it Dynamotion Fit — which is designed to mimic the foot’s skin, stretching and compressing with it during a run. The fabric is light and airy, and it gives the shoe’s upper a comfortable, sock-like feel. On hot-weather runs, the upper’s mesh construction let heat escape and prevented moisture from building up within the shoe.<br /></font></font><br /><font size="2"><font face="Verdana,sans-serif">A few weeks after running in the Wave Prophecys, I went back to my old running shoes with the EVA cushioning. I thought I’d appreciate the extra padding, but the old shoes felt too soft. I felt as if I was getting less distance out of every step, sort of like running in mud. <br /></font></font><br /><font size="2"><font face="Verdana,sans-serif">After getting used to the responsiveness of the Prophecys, my feet were begging to go back. It was like driving a Porsche, then suddenly being asked to swap it for a crappy old minivan. I’ll stick with the Porsche.<br /></font></font><br /><strong><font size="2"><font face="Verdana,sans-serif">WIRED</font></font></strong><font size="2"><font face="Verdana,sans-serif"> Stiff, dual-plate midsole system gives a subtle snap to every step. Responsive, comfortable upper. Potentially the most durable running shoe ever.<br /></font></font><br /><strong><font size="2"><font face="Verdana,sans-serif">TIRED</font></font></strong><font size="2"><font face="Verdana,sans-serif"> May be too firm for some runners. Potentially the most expensive running shoe ever.<br /></font></font><br /><font size="2"><font face="Verdana,sans-serif"><br /></font></font> |   
 
 
 
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