September 28, 2005
Cracking the code for hurricane forecasts
In light of the hurricane issues our country has been having, I found it appropriate to write about it. This MSNBC news article gave a little information on the tracking of hurricanes and how to read what they are telling us.
Hurricane prediction experts are saying that if you just look at the "skinny black line" when watching a predicted hurricane, it's not enough to tell you where and how hard the hurricane will hit. The National Hurricane Center has a new tool that narrow down where it is likely a hurricane will hit and how strong the winds may become. They comment that these new developments are for saving lives, no matter how scientifically interesting they may be.
Hurricane pictures show a "balloon" because it balloons outward from where the storm's position may be three to five days in the future. In order to get these predictions at all, forecasters have to take data such as wind, precipitation, temperature and pressure from air and ground resources and put all of them into computer systems in order to study them. They then come up with specific forecasts that predict a storm's certain location at a certain time. All these forecasts added together form the "skinny black line" and from there, the forecasts can add the "cone of uncertainty by mathematically computeing an error range, based on a 10-year average of prediction errors." I find it interesting that the entire hurricane is based on a computer and past errors in order to warn thousands of people their lives may be in danger. As the cone widens around the black line, it is getting further away in time because these predictions are more likely to be wrong the more in the future they are.
If you want to look at these forecasts, the National Hurricane Center has all of these tools on their webpage. Their graphics include a three day cone and a five day cone; it is historically shown that a given storm has 60 to 70 percent change of staying within the cone when looked at on a three day cone map. They are saying it's more important to focus on the balloon shaped areas rather than the black line because storms do take unexpected turns. All of the uncertainty a hurricane provides in basically a scary thing for the people who it affects. Those paying attention to the large area are more likely to be aware of a storm that could possibly hit their area at a given time, though the black line is still important. It gives a general "danger zone" and can be effective that way. This new development is able to make people aware of the storms in their area and can possibly save lives when people are paying attention to what is going on.
The black line chart is a probability chart. It shows the probability that the center of a storm will pass within 75 miles of the given point during a 72 hour period. This tool also shows strike probabilities and can give an estimate of when the storm will affect your area, using 12 to 24 time periods.
An obvious important hurricane factor is the wind. The prediction maps are a little more difficult for wind, but for a tropical storm, the service provides "three maps displaying the likelihood that sustained winds in a given area will exceed a particular level over periods of up to five days."
Though these tools are available at a national level, the areas that are in direct paths of the storm should obviously pay attention to their local weather and grasp information that way. I just feel that these tools could be very helpful for people who live in other areas and have loved ones living in storm paths. It helps us be aware of what is going on, because in the Midwest we aren't as affected as those down south. Katrina is a national problem, and in the future these new discoveries may help natural disasters be somewhat less, well, disastrous.
Posted by at September 28, 2005 8:53 PM | 2. In the News