State hazard mitigation plans guide state and local agencies in actions they may take to reduce their vulnerability to extreme events. However, because they are written for a general audience, they must be written in a way for a layperson to understand. In many cases, the people writing these plans are not meteorologists or do not have access to meteorological expertise. Consequently, descriptions of hazards may be taken from websites, other documents, or perhaps authoritative sources. This leads to inconsistencies in the way hazards are portrayed in the plans, which increases the difficulty of translating proposed actions to local governments or to other states.
This article delves into the issue of these variances and how it affects those who write state hazard mitigation plans. For this brief text, the hazards discussed in state plans that fall in the National Oceanic and Atmospheric Administration (NOAA) Regional Integrated Sciences and Assessments (RISA) Southern Climate Impacts Planning Program (SCIPP)’s region are covered with a comparison of definitions from the National Weather Service (NWS) and the American Meteorological Society (AMS). States within the SCIPP region include Oklahoma, Texas, Arkansas, Louisiana, Mississippi, and Tennessee. This study found that it is more common for states to use key words from NWS and AMS hazard definitions than to use exact definitions. The goal of this article is to prompt a discussion about the inconsistency of terminology used in state hazard mitigation plans and to spread awareness of this issue so that future plans can keep their unique elements while providing a better description and understanding of the included hazards.
State hazard mitigation plans guide state and local agencies in actions they may take to reduce their vulnerability to extreme events. However, because they are written for a general audience, they must be written in a way for a layperson to understand. In many cases, the people writing these plans are not meteorologists or do not have access to meteorological expertise. Consequently, descriptions of hazards may be taken from websites, other documents, or perhaps—in rare cases—authoritative sources. This leads to inconsistencies in the way hazards are portrayed in the plans, which increases the difficulty of translating proposed actions to local governments or to other states. Inconsistencies in definitions create several problems. First, if a problem is not accurately specified, then solutions may not fully address the issue. Second, with different sources used for these definitions, it makes transferability from one jurisdiction to another more difficult. Finally, having a variety of definitions may impede the review process from the Federal Emergency Management Agency (FEMA).
This article delves into the issue of these variances and how it affects those who write state hazard mitigation plans. For this brief text, the hazards discussed in state plans that fall in the National Oceanic and Atmospheric Administration (NOAA) Regional Integrated Sciences and Assessments (RISA; Pulwarty et al. 2009) Southern Climate Impacts Planning Program (SCIPP)’s region will be covered with a comparison of definitions from the National Weather Service (NWS) and the American Meteorological Society (AMS). States within the SCIPP region include Oklahoma, Texas, Arkansas, Louisiana, Mississippi, and Tennessee. The goal of this article is to prompt a discussion about the consistency of terminology used in state hazard mitigation plans and to spread awareness of this issue so that as states begin updating their plans, they will work together to keep their unique elements while remaining complimentary to each other.
Hazards vary across state hazard mitigation plans, according to the risks that each state predominantly faces. Even though states in the SCIPP region face many common risks, there are some hazards that are not mutual across the board. For example, hurricanes and tropical storms are important hazards that affect the coastal states but not inland states such as Tennessee. Weather-related natural hazards that are included in each SCIPP state are floods, tornadoes, drought, and wildfire. State officials must decide upon which hazards to focus, and so some hazards that do not affect the state to a significant magnitude are not included in the plan. Hail was a hazard that was included in all plans except Mississippi. They stated that while it is a risk, it is not a great enough threat to include it in their hazard discussion. Other meteorological hazards included in the plans are winter storms and extreme heat, but they are not easy to define because they are dependent on geographic location. For example, extreme heat in Wisconsin would differ from what is considered as extreme heat in Texas. This is also true of winter storms, since a particular amount of heavy snowfall in the northern United States would not impact that region the same as the equivalent snowfall amount would affect a southern state. These examples reflect another issue of how to define an extreme event, which is not discussed in this study.
To begin this analysis, all meteorological hazard definitions were collected from each state hazard mitigation plan in the SCIPP region. To remain consistent, only the hazards used in all states’ plans were included in the comprehensive analysis. Hazards that were defined by the AMS or NWS and are present in some, but not all, SCIPP state hazard mitigation plans are provided in Table 1. After determining which hazards were collectively used, each definition was compared to the AMS definition as well as the NWS definition (Table 2). These four hazards included floods, tornadoes, drought, and wildfire. Note that the AMS does not define wildfire, so this hazard was only compared to the NWS definition. The AMS and NWS were chosen for this study based on different merits. The AMS is a very large professional organization that has prominence in the field of meteorology and an easily accessible glossary of terms. It represents an authoritative scientific source. The NWS is a government entity that has a close connection to the public as well as the emergency management community. The NWS issues warnings for some of these hazards, such as flash floods and tornadoes, so emergency managers should already be familiar with how the NWS defines these hazards. This source provides an operational perspective. To be fair to the states, two questions were asked. Was the exact AMS or NWS definition used? Were key words from AMS or NWS definitions used? There was only one instance of a state using an exact definition, so it was necessary to record the number of definitions that portrayed the overall concept with accurate key words.
There were mixed results for this project. Only Mississippi used an exact NWS definition of drought, and there were no AMS definitions in the plans. This was slightly concerning in that there were such inconsistent definitions (Table 3). The analysis of the number of definitions that included key words from the AMS or the NWS conveyed more promising results. Of the 18 possibilities, there were 10 definitions that incorporated key words from the AMS definition and 16 out of 24 from the NWS (Table 4). Note that these numbers only include the number of definitions with key words, not the number of key words.
Of the four hazards collectively presented in the plans, it is clear that definitions vary across the states; 0% to 4% of exact definitions were introduced in the plans, and there were no clear citations in the documents to show where the chosen definitions originated from. It was reassuring to see that 56%–67% of the definitions included key words from the recommended sources. However, when looking at individual definitions, some incorporated key words to remain consistent with terminology but still did not achieve a high-quality definition. For example, all state definitions of a tornado used NWS key words and most used AMS key words as well. Key words that were identified for this definition included “rotating,” “violent,” “column,” “funnel,” and “ground.” Were the definitions exemplary? Not always. The AMS defines a tornado as “a rotating column of air, in contact with the surface, pendant from a cumuliform cloud, and often visible as a funnel cloud and/or circulating debris/dust at the ground” (AMS 2015), and the NWS defines it as “a violently rotating column of air, usually pendant to a cumulonimbus, with circulation reaching the ground. It nearly always starts as a funnel cloud and may be accompanied by a loud roaring noise” (NWS 2009).
All state definitions incorporated a word use of violently/rapidly rotating, funnel, and cloud. Tennessee’s definition was closest in comparison to the NWS definition, stating, “A tornado is a violently rotating column of air, pendant from a cumuliform cloud or underneath a cumuliform cloud and often (but not always) visible as a funnel cloud.” While this definition is almost an exact one, it leaves out a crucial concept that the circulation must reach the ground to be classified as a tornado. Even though many states used key words from AMS or NWS definitions, many of their definitions did not quite meet the expectations of a state government document. For example, Louisiana defined a tornado as “rapidly rotating funnels of wind extending between storm clouds and the ground,” and Mississippi stated that a tornado is “a rotating, funnel-shaped cloud that extends from a thunderstorm to the ground with whirling winds that can reach 300-miles per hour.”
While these definitions may characterize the general concept, government officials should be encouraged to apply the proper terminology in their state hazard mitigation plans that are used by the emergency management community and city planners. Berke et al. (2012) analyzed multiple state mitigation plans across the U.S. coasts and evaluated them based on six scoring criteria. The authors found that many had a low score on the fact-based portion of the evaluation, including a poor quality of hazard description. States can take this into consideration and create consistent definitions that reflect a more factual description to better their score.
These results have only included hazards that affected all states; however, the trend of information described above is exhibited in the other hazards as well. All states that declared tropical storms/hurricanes as a hazard predominantly used key words from the NWS, and hail was defined using key words from both the NWS and the AMS definitions.
This study found that the overall trend of information included the use of key words from the NWS’s hazard definitions more than definitions from the AMS. However, the use of key words did not always produce accurate or well-executed definitions from the state hazard mitigation plans. The NWS is a highly visible government entity with an active outreach program to the emergency management community. Thus, it is viewed as an authoritative source for those developing and implementing hazard plans. As a professional organization, the AMS may not be as well known to those outside the field of meteorology, perhaps contributing to less consistency with AMS definitions. Furthermore, AMS definitions are more technical than those of the NWS, as an essential condition for defining research.
For the purpose of state hazard mitigation plans, the authors suggest the use of definitions from the NWS because the terminology may be more easily conveyed to emergency managers and city planners. As stated previously, effective communication of the appropriate terminology in hazard definitions is often lacking, even with the use of key words. Some officials may not use exact definitions because they may not fully understand all aspects of the definition or only use the segment that seems most relevant to their plan. For example, the phrase “pendant from a cumuliform cloud” from the AMS may be a technically accurate and important part of the definition, but for purposes of hazard planning this detail may not be important. While states and plan developers need flexibility to adapt the plan to their unique circumstances, they must assure that such definitions are technically accurate, complete, and convey essential concepts to the intended audience. Thus, a low score on direct matches may be fine, but a low score on key-word matches could be problematic. They must ensure that the emergency managers and city planners have a full understanding of the risks that are likely to affect their state. The purpose of this study is to bring these inconsistencies to the attention of state officials and ensure that hazard descriptions in these plans are technically accurate but flexible enough to reflect state and local needs. The authors are hopeful that this analysis will start a dialogue between the NWS and those that create and update state hazard mitigation plans, as well as emergency managers, to ensure that the hazard definitions and descriptions are accurately portrayed and better understood.
The authors would like to thank the Southern Climate Impacts Planning Program hosted at the Oklahoma Climatological Survey in Norman, Oklahoma, for their aid with graduate pursuits at the University of Oklahoma. This study was funded by a grant from the NOAA Regional Integrated Sciences and Assessment (RISA) Program from NOAA’s Climate Program Office under Cooperative Agreement NA13OAR4310183.