ScienceDaily (Apr. 17, 2008) — The Earth's jet streams, the high-altitude bands of fast winds that strongly influence the paths of storms and other weather systems, are shifting--possibly in response to global warming. Scientists at the Carnegie Institution determined that over a 23-year span from 1979 to 2001 the jet streams in both hemispheres have risen in altitude and shifted toward the poles. The jet stream in the northern hemisphere has also weakened. These changes fit the predictions of global warming models and have implications for the frequency and intensity of future storms, including hurricanes.
Cristina Archer and Ken Caldeira of the Carnegie Institution's Department of Global Ecology tracked changes in the average position and strength of jet streams using records compiled by the European Centre for Medium-Range Weather Forecasts, the National Centers for Environmental Protection, and the National Center for Atmospheric Research. The data included outputs from weather prediction models, conventional observations from weather balloons and surface instruments, and remote observations from satellites.
Jet streams twist and turn in a wide swath that changes from day to day. The poleward shift in their average location discovered by the researchers is small, about 19 kilometers (12 miles) per decade in the northern hemisphere, but if the trend continues the impact could be significant. "The jet streams are the driving factor for weather in half of the globe," says Archer. "So, as you can imagine, changes in the jets have the potential to affect large populations and major climate systems."
Storm paths in North America are likely to shift northward as a result of the jet stream changes. Hurricanes, whose development tends to be inhibited by jet streams, may become more powerful and more frequent as the jet streams move away from the sub-tropical zones where hurricanes are born.
The observed changes are consistent with numerous other signals of global warming found in previous studies, such as the widening of the tropical belt, the cooling of the stratosphere, and the poleward shift of storm tracks. This is the first study to use observation-based datasets to examine trends in all the jet stream parameters, however.
"At this point we can't say for sure that this is the result of global warming, but I think it is," says Caldeira. "I would bet that the trend in the jet streams' positions will continue. It is something I'd put my money on."
The results are published in the April 18 Geophysical Research Letters.
It's Severe Weather Week
Severe Weather Awareness Week takes place April 21-25 this year, with the statewide tornado drills Thursday.
At 1:45 p.m. Thursday, the National Weather Service will issue a simulated tornado warning, and outdoor warning sirens will be activated. At 6:55 p.m., a second drill will take place in Scott County for families and second-shift workers.
“Everyone should practice their safety plans during Severe Weather Awareness Week,” said Chris Weldon, Scott County emergency management director. “There is no pattern to these things. A tornado can happen any day — without warning — and your preparation time is well spent.”
According to National Weather Service data, tornadoes have occurred in every Minnesota county at some time during the past 57 years. Scott County has experienced 12 tornadoes since 1950.
The Minnesota Department of Public Safety Division of Homeland Security and Emergency Management, along with the National Weather Service and the American Red Cross, sponsors Severe Weather Awareness Week annually to promote weather knowledge and planning. The Web site at www.severweather.state.mn.us, contains tornado safety information along with instructions on surviving thunderstorms, hail, straight-line winds, heat waves, floods and lightning. Links to the National Weather Service and Red Cross provide fascinating weather facts and a variety of downloadable resources for families, teachers and children.Citizens prepped on disaster response
BY MICHAEL OPPERMANN
SPECIAL TO THE STAR-BANNER
OCALA — Marion County government, taking a proactive approach to terrorism, hosted a three-day training course under a grant from the Department of Homeland Security. Successful completion of the course, and an associated online component, granted educational credit to those who passed, better preparing them to respond to the possibility of terrorist events.
From Tuesday to Thursday, two instructors from the Texas Engineering Extension Service trained locals in recognizing, responding to and recovering from terrorist incidents.
The course, "Public Works: Planning for and Responding to a Terrorist/WMD Incident," was designed to help integrate training for terrorist events into existing emergency response plans.
Byrd Wilcox, safety hazard coordinator for the Public Works Bureau, said that while every emergency situation is unique, they all have common elements. Hurricanes, fires, chemical spills and terrorist threats can all be handled using the same crisis management techniques.
"All that this class is teaching the participants is that no matter how small or big [an event] is, it uses the same process," Byrd said.
Instructors Luke Stevens and David Pullen, both longtime public works officials, spent much of the course time discussing how communities react to emergencies and analyzing government response to previous terrorist events.
"One way we learn is from our own experiences. If we do that, then the depth of our knowledge will be limited by our experiences," Pullen said. "If we can learn from other people's experiences, then we broaden our knowledge and broaden the probability of a successful outcome."
Luiz Bisacchi, principle business analyst for public works in Hillsborough County, agrees, having attended the course to aid in the development of his community's hazmat protocols. "The Oklahoma case study was very helpful," he said. "Hopefully I can take some of [what I learned] back home and apply that to our plans."
COMMUNICATION IS KEY
Hot-button issues during the course were communications during an emergency situation and the integration of various agencies into the emergency response.
Lawrence Thacker, Marion County Public Works Bureau Chief, taught the course five years ago, and said that responding to an emergency "takes a lot of communication and a lot of coordination." The inability to do so complicates emergency situations and reduces the effectiveness of recovery efforts.
He feels the most effective way to safely deal with a crisis situation is to develop response plans well in advance and train workers in implementation of those plans.
"Safety is important to me because of my background," Thacker said. "I spent 18 years working underground in coal mines. I know what it is like when you've got your employees with you and you're trapped for 36 hours."
Attendee Andrea Nelson, of the transportation department's Public Education and Outreach section, is aware of the importance of effective communication.
"In a designated emergency I'm assigned to a public information function," she said, "so I think it's always good to know how your area will be interacting with others."
Nelson feels that increased training over the last few years has prepared government employees to better deal with emergencies.
"Setting up an incident command, determining who is in charge, identifying the functions that have to be filled and filling those, I think everyone here has been through the basics of that," she said.
Integration of services into a single command and communication structure is equally as important. While many note the disaster relief contributions of police officers, firemen and EMS personnel, they often overlook the contributions of public works employees and volunteers.
Stevens believes 90 percent of an emergency situation involves people from public works.
"Most people who look at an incident are looking at the initial response; it is putting everything back together that is the hardest part. The more that public works is involved, the better off you're going to be," he said. "Either the community is going to respond well together, or everybody is going to lose."
Robert Middleton, senior litter crew supervisor for solid waste, knows the value of integrating his efforts with an emergency response plan.
"We have a plan in place for natural disasters and terrorists," Middleton said. By preparing now, his people will be ready to fulfill their role when called to respond to an emergency situation.
Wilcox said volunteers can be valuable assets in an emergency situation, but only if they are correctly integrated into the response plan. "Volunteers need to be trained and credentialed," he said.
Having people show up at a disaster site without going through proper channels disrupts the command structure and lines of communication, leaves people working at cross-purposes and potentially turns would-be volunteers into victims. Unstable ground, overhead debris, toxic fumes and other hazards can injure or kill the unprepared.
Wilcox suggests that members of the public who want to become involved in disaster response should follow the example of county government and plan ahead. Citizens should prepare disaster supply kits of food, water, flashlights and other necessities and review shelter-in-place and evacuation procedures that can be found on the Internet.
Proactive citizens also can join organizations such as the Red Cross, Salvation Army, Citizen Corps and Amateur Radio Emergency Service.
A salvage company is being sought to recover a tanker truck and logging equipment that sank to the bottom of Robson Bight, off northern Vancouver Island, last August.
A tugboat was used to move a barge that overturned in Johnstone Strait last August.
A barge carrying the truck and equipment capsized in Johnstone Strait, an ecological reserve for killer whales.
B.C. Environment Minister Barry Penner said his government is concerned that leaking fuel may pose a threat to orcas and other marine life.
Penner and Loyola Hearn, Federal Minister of Fisheries and Oceans, announced Friday that they have decided to attempt a recovery operation following months of debate over what to do about the wreckage.
Penner said the first priority is to go after the equipment that contains the most fuel.
The barge was pushed to shore by the tugboat near Beaver Cove.
"That would be the fuel truck that had a tank that could hold up to 10,000 litres of diesel fuel," he said. "There's also a piece of equipment that we believe contains a significant amount of hydraulic fluid."
Penner said only a handful of companies in North America have the expertise to do the job.
The minister said the plan is to retrieve the equipment as quickly as possible, while minimizing From Holland and Knightthe impact on wildlife.
He said recent video footage of the sunken equipment shows it to be in decent shape.
Legal Notes From Holland and Knight
The US Coast Guard issued a press release reminding mariners that older model Emergency Position Indicating Radio Beacons (EPIRBs) that broadcast on 121.5 MHz or 243 MHz will not be monitored by satellite as of February 1, 2009. Effective that date, the satellites will only monitor for radio beacons broadcasting on 406 MHz. Some of the newer EPIRBs are equipped with embedded GPS, which will automatically signal the location of the distress. (4/18/08).