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Scientific Advancements and Limitations
Scientific understanding of atmospheric processes, though highly advanced, is incomplete and imperfect. While much is known about hurricanes, far more remains to be discovered.
Sources of Scientific Progress
Meteorology, or atmospheric science, is a branch of intermediate-scale physics. The tropical subcategory of meteorology, which studies hurricanes and tropical weather in general, derives its equations of hurricane motion and thermodynamics from Newton's laws. As Newtonian science has been around for a very long time, the physical conditions in the atmosphere that allow for hurricane formation, the mechanics of the hurricane's motion through space, the structure of this type of storm, and the thermodynamic processes that characterize it, are reasonably well understood by today's science.
This body of knowledge is incorporated into various numerical models, so called because they are used to model or simulate complex processes taking place in the atmosphere. The equations used in the models are programmed into supercomputers, which solve them using various types of weather data as input. In this manner, they can produce simulations of atmospheric processes that are of great value to human forecasters, who use the output as guidance.
| Model | Description |
| HWRF | Hurricane Weather Research Forecast Model |
| GFDL | Geophysical Fluid Dynamics Labarotory Model |
| UKM | UKMET Model |
| NGPS | NOGAPS Navy global numerical model |
| AVNO | GFS Model |
| BAMD | Beta and Advection model (deep) |
| CLP5 | Climatology and Persistence 5-day (control model) |
The various models all have their own strengths and weaknesses, some of which may become more pronounced under certain conditions, or even with regard to a particular storm. Individual atmpospheric models are therefore sometimes combined into ensembles to diminish the impact of whatever quirks or biases any one model may have. There are also some models that are used for very specific tasks (the GFDL was developed specifically to provide forecast guidance on the tracks of hurricanes), or for control purposes (the CLIPER model is used as a baseline for measuring the skill of official forecasts and of other forecast models). Tropical research meteorologists also use model simulations of hurricanes to help them answer specific research questions currently under discussion in their science.
Scientific Limitations
Thus have advancements in scientific understanding, observational equipment such as satellites, and computer technology all contributed to the recent advancements in the science of hurricane forecasting. Yet despite all the advancements, central theoretical questions remain to be resolved.
Scientists don't fully understand, for example, the process of tropical cyclogenesis (genesis of tropical cyclones). They don't know precisely how it occurs, or why some tropical disturbances generate into hurricanes, while others, which may meet all the known requirements for hurricane formation, fail to develop. Part of the difficulty in answering such questions is the logistical dilemma of how to take measurements over distant and vast open oceans, especially in the ocean layer just beneath the storm, and at the boundary where the ocean meets the atmosphere.
Scientists also do not fully understand, for instance, why some hurricanes undergo the process of rapid intensification or "explosive deepening" of their low pressure centers. They know that it appears to be related to the eyewall replacement cycle, in which an outer eyewall forms around the original eyewall, starves of it of energy, and then ultimately replaces it, and that a significant number of storms which go through this process also undergo rapid intensification. Research efforts in this area are ongoing, as part of the drive to better understand and model the physics governing the intensification of hurricanes, and thus, bring about new advancements in intensity forecasting.
It is well known that some hurricane seasons are more active than others. Some of the physical processes that account for these seasonal variations in hurricane activity are now understood, such that it is now possible to forecast an active season or an inactive one with a higher degree of accuracy than could be produced from climatology alone. The pioneer in this area is Dr. William Gray, the renowned tropical research meteorologist at Colorado State University, who has, together with his successors, been releasing his seasonal hurricane forecasts to the public in recent years.
As with the problem of tropical cyclogenesis, the conditions associated with more or less active seasons have been identified and are known, but it is still not within the capabilities of modern science to predict exactly how many storms will form in a given year, where and when they will form, and most importantly, whether, where, and when they will make landfall.
In addition to these highly specific limitations, chaos theory, a seminal late-20th century development in intermediate-scale physics, may impose a theoretical outer limit on the ability of any science to predict the future states of complex systems such as the Earth's atmosphere. While the theory's inventor, Edward Lorenz, was himself a meteorologist, thus identifying its meterological origins, the implications of this theory have long ago transcended meteorology. Chaos theory has had a permanent impact not only on other branches of physics but on other domains of inquiry altogether, including mathematics and even human affairs.
Scientific precision is also limited by practical considerations, such as technology and cost constraints. Computers are still not fast enough to handle the vast amounts of data the atmosphere can supply, nor can they, even today, operate at the micro-resolutions that might be required to model such finely-grained processes as those that might control the intensification of hurricanes. Observations often have to be made indirectly, such as through remote sensing (satellites), as direct measurements are difficult to obtain in places where hurricanes are active, especially over the open ocean and directly beneath the storm circulation. Even where it is possible for them to reach, measuring instruments can be spaced only so closely together, and observations can be taken only so frequently, thus limiting the resolution of observational data both in space and in time.
And finally, the budget for hurricane research and the associated personnel and equipment is not unlimited; at times of national economic hardship, budgetary priorities may threaten even existing capabilities.
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