[ti:California to Develop Earthquake Early Warning System] [by:蜗蜗牛小游戏网 www.liandama.cn] [00:00.00]更多听力请访问www.liandama.cn [00:00.01] Californian officials say they will spend more than $40 million on an earthquake early warning system. [00:09.10]The announcement comes after two powerful earthquakes shook parts of the state last week. [00:17.85]On Thursday, a 6.4-magnitude earthquake struck an area in the Mojave Desert, but the effects could be felt as far away as Los Angeles. [00:32.36]Then on Friday, a 7.1-magnitude earthquake struck near Ridgecrest, California, causing damage to houses and roads. [00:45.92]The proposed early warning system would let the public know of a possible quake. [00:53.15]Officials say it also would automatically halt trains and open fire station doors moments before a major quake strikes. [01:06.50]California Governor Gavin Newsom made an announcement after Friday's quake. [01:14.28]He said that the state has already put in place 70 percent of 1,115 sensors needed for a statewide system. [01:28.39]Ryan Arba is with the governor's Office of Emergency Services. [01:36.29]He said, "I think the whole state's on notice right now about the opportunity that's in front of us." [01:46.32]Emergency officials have said they hope to have the statewide warning system in place by the middle of 2021. [01:58.49]The recent strong earthquakes were the first in 20 years in Southern California. [02:06.59]They brought increased attention to the development of the state's early warning system. [02:14.16]Japan developed the world's most modern earthquake early warning system after the 1995 Kobe earthquake. [02:25.77]It relies on more than 4,000 sensors and is based on the same laws of physics that California is using to build its system. [02:38.96]As in Japan, the California system is designed to detect the fast-moving seismic P-waves that are produced by earthquakes. [02:52.61]These waves can reach a sensor before the ground starts moving. [02:58.72]The U.S. Geological Survey says that many animals are able to feel P-waves. [03:07.08]Communities farthest from the epicenter of a quake would receive the earliest warning. [03:15.67]Arba says, for example, that a quake on the San Andreas Fault near California's border with Mexico [03:25.49]would give Los Angeles 60 seconds of warning before the ground began to shake there. [03:34.04]However, communities very close to a quake's center would receive little or no warning. [03:42.95]Officials in Los Angeles County in January introduced a "ShakeAlertLA" mobile phone application. [03:54.28]It can send an early warning to residents who have the app. [03:59.97]The "ShakeAlertLA" app, however, was not activated for either of the recent quakes. [04:08.24]The U.S. Geological Survey said this was because they were not strong enough. [04:15.62]The Bay Area Rapid Transit (BART) system in and around San Francisco has connected the early detection system to its rail service. [04:28.88]The system is designed to automatically slow down trains, Arba said. [04:35.64]Southern California's Metrolink commuter rail system halted service after Friday's 7.1 earthquake in Ridgecrest. [04:48.57]But, a spokesman said orders to stop the trains only went out by radio [04:56.70]when shaking was felt by officials at the operations center in Pomona, east of Los Angeles. [05:05.94]The Metrolink board has voted to spend $4.9 million in public money [05:15.62]to automate the halting of its trains when a quake is detected, the spokesman said. [05:22.78]University of California at Los Angeles engineering professor John Wallace said there are many possible uses for the early warning system. [05:36.80]"Once you provide the system, you'd be surprised how many ways people will find to use it," he said. [05:46.97]I'm Mario Ritter Jr. 更多听力请访问www.liandama.cn