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Review Article: Wind and storm damage: From Meteorology to Impacts

Authors:
Daniel Gliksman at Hebrew University of Jerusalem
Daniel Gliksman
Paul Averbeck at Rheinland-Pfälzische Technische Universität Kaiserslautern-LandauRPTU
Paul Averbeck
  • Rheinland-Pfälzische Technische Universität Kaiserslautern-LandauRPTU
Nico Becker at Freie Universität Berlin
Nico Becker
Barry Gardiner at Institut Européen de la Forêt Cultivée
Barry Gardiner
  • Institut Européen de la Forêt Cultivée
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Abstract

Wind and windstorms cause severe damage to natural and human-made environments. Thus, wind-related risk assessment is vital for the preparation and mitigation of calamities. However, the cascade of events leading to damage depends on many factors that are environment-specific and the available methods to address wind-related damage often require sophisticated analysis and specialization. Fortunately, simple indices and thresholds are as effective as complex mechanistic models for many applications. Nonetheless, the multitude of indices and thresholds available requires a careful selection process according to the target environment. Here, we first provide a basic background on wind and storm formation and characteristics, followed by a comprehensive collection of both indices and thresholds that can be used to predict the occurrence and magnitude of wind and storm damage. We focused on five key environments: forests, urban, transport, agriculture, and wind-based energy production. For each environment we described indices and thresholds relating to physical properties such as topography and land cover but also to economic aspects (e.g. disruptions in transportation or energy production). In the face of increased climatic variability, the promotion of more effective analysis of wind and storm damage could reduce the impact on society and the environment.
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Nat. Hazards Earth Syst. Sci. Discuss., referee comment RC1
https://doi.org/10.5194/nhess-2022-159-RC1, 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
Comment on nhess-2022-159
Anonymous Referee #1
Referee comment on "Review Article: Wind and storm damage: From Meteorology to
Impacts" by Daniel Gliksman et al., Nat. Hazards Earth Syst. Sci. Discuss.,
https://doi.org/10.5194/nhess-2022-159-RC1, 2022
Summary
According to the title, this manuscript addresses the topic of wind and storm damage from
the genesis of meteorological conditions that lead to storms to the damage that storms
can cause. In my view, the title of the manuscript is too general, as the authors focus on
extra-tropical storms and their impacts over the North Atlantic-European region. One can
clearly see that the review was written from a European perspective. Therefore, I suggest
a title change that more closely reflects the focus of the manuscript and the spatial
relevance of the summarized studies. An imbalance can also be observed concerning the
five sectors studied. The text portions in which wind effects on forests and trees are
described predominate. This is not unfavorable in principle but should be clarified in the
introduction.
In the following, I list comments on peculiarities of the manuscript that I noticed during
reading:
General comments
- I suggest providing definitions (e.g., based on numerical values, duration, …) of “wind”,
“windstorm”, “storm”, “wind-related risk”, “gust”, “mean wind speed”, … early in the
Introduction. In the context of “wind-related risk assessment” this is important. What is
“wind-related risk”? Is this wind and storm damage risk? Not all wind speed values pose a
risk and cause calamities.
- I suggest deleting “e.g.” when citing other studies (e.g. P2L57 “e.g. Bittelli et al., 2008)
throughout the text.
- I suggest homogenizing the citations style in the text. Please pay attention to the use of
the comma and semicolon.
- Please homogenize and correct the order and formatting of all citations in the text. I
found different formats and orders (by authors vs by year).
- Please check the formatting and grammar of all headings.
- Please insert a blank character between numbers and units wherever it is missing.
- Please add more line breaks where new trains of thought begin.
- I suggest a complete review of the formatting of abbreviations and symbols. Particular
attention should be paid to the subscript of letters.
- It seems as if sections were written by different authors. There are discernable
differences in the diction, and other inconsistencies:
- Please make sure that there are no repetitions of definitions or basic facts in different
sections. For example, “wind load” sure be defined once at the very beginning, not in
sections 4.3.
- The sections have a differing structure of subsections. I suggest using the same or a
similar structure and contents in the sections. This considerably increases the readability
of the long manuscript.
- I suggest moving all knowledge, facts, concepts, and descriptions (e.g., structure of the
lower parts of the boundary layer, wind pressure, vertical wind profile, coherent
structures, roughness, porosity, channeling, codes, terrain roughness, orography index vs
topography index, …) that are portable to all “environments” are provided in separate
sections before presenting the specifics of the environments.
- Please check the entire text for the incorrect use of uncountable nouns such as damage
and wind speed.
Specific comments
L43: What is the difference between wind damage and storm damage? What is the metric
that is used to distinguish the two kinds of damage?
L50: I suggest using the correct technical term “air temperature” instead of
“temperature”.
L66: What is the difference between “strong winds” and “strong wind gusts”? I suggest
providing clear definitions of both quantities.
L67-L75: At this point it would make sense to introduce the definition of risk. The storm
damage risk is the product of hazard, exposition, and vulnerability.
L75: I suggest better structuring and formulating the list “wind, storm dynamics, and the
ability …” What is the meaning of “understanding wind”?
L81: Do you solely mean “wind damage”? Or also storm damage? I suggest replacing
“wind-damage” with “wind damage”.
L82-L86: I suggest deleting all repeated information that has already been provided in
previous lines.
L92: Please replace “in the Earths’” with “of the Earth’s”.
L103: Please delete the superfluous “below”.
L110: I suggest lower casing “Northern”, “Southern” and “Hemisphere”.
L117-L123: These lines are located between explanations about the jet stream. Therefore,
I suggest moving these lines further down and to merge the information about the jet
stream. It would also make sense with respect to the space and time scales that boundary
layer processes dominate to move the lines downward.
L136-L144: It is not clear why these explanations are provided. I doubt that the entire
readership knows how “vorticity” is defined. Where is the connection to air motion in the
context of this paper?
L147: I suggest replacing “its” with “their”.
L195: Please adjust the formatting of the heading to the formatting of the other headings.
L200-L201: I suggest deleting the lumped references. They are repeated in the following
lines.
L206: “CMIP5” is undefined. I suggest providing a definition.
L211: Please correct the heading’s formatting. Why are “Circulation Characteristics”
capitalized?
L222: Please provide a definition of abbreviation “ERA5”.
L223: Please homogenize the information on the geographical coordinates.
L230: I suggest lower casing “Sea Level Anomalies”.
L232: Please insert a blank character between “250” and “hPa”.
L234: Is it necessary to display the sequence of weather regimes (CL1-CL5)? I suggest
deleting Fig. 1c. It does not provide information needed for this review.
L235: Is “red arrow” correct? I do not find a red arrow.
L235: What is “eXtreme WindStorms”? Is this an expression needed for this review?
L236: Please replace “storm track for storm” with “track for storm” or “storm track of
Klaus”.
L235: Please add the missing dot after “al”.
L229-L256: Please homogenize the use of quotation marks when referring to winter storm
Claus.
L244: Please replace “5” with “five”.
L252: The citations “Liberato et al., 2011” can be deleted. It is used again in L256.
L254, L262: Is “jet-stream pattern” the same as “jet regime”, as used on P6L232? If so, I
suggest homogenizing the technical terms to minimize the load of specialized speech.
L258-L262: When looking at Fig. 1c, I find many CL4 regimes where no severe storm has
occurred. In my opinion, this considerably relativizes the statements made here regarding
specific weather regimes. I therefore suggest deleting or at least reformulating these
lines.
L264: Please check the grammar. Is this the right case? Please lower case “Seasonal
Variability”.
L270-L271: What is a “wind interval”? Do you mean “wind speed interval”? Please clarify.
L272-L273: The reference of the relative pronoun is ambiguous. Please considering
rephrasing this sentence.
L274: There is no definition of “WL3” and “WL4”. Please provide more details.
L282-L283: Please provide correctly formatted tildes.
L286: Please homogenize the spelling of “intraseasonal”. What is your definition of
“intraseasonal”? For me, this is the variation of wind speed within one season, e.g.,
winter. Is this the same definition for you? Or do you mean “intra-annual”, which is the
variation of wind speed between seasons over the year. Please clarify.
L312: Why is “speeds” provided in km/h? Previous “speed” values were provided in m/s?
Please homogenize. Which “speeds” do you mean? Wind speed or gust speed or anything
else? Please clarify.
L314: Please check the double use of “from”.
L316: What do you mean by “commonly”. Can this be quantified?
L317: Which “type of convective activity” do you mean? And why is the reference
Diffenbaugh et al. (2013) older than the references that refer to “more commonly
reported”. This is not stringent.
L328: What are “wind field” characteristics that are relevant for this review besides
“speed”. Please be more specific.
L329-L330: Please delete “caused by wind”. It is redundant.
L335. Please homogenize the spelling of “earth” throughout the text.
L351: Please homogenized the spelling of “wind speed” vs “wind-speed” in the text.
L367-L377: There are still no generalizable findings on whether the effect of individual
tree stability or that of collective stand stability better protects forests from storm
damage. Kamimura et al. (2022, listed in the References) provide important insights in
this regard. They should be mentioned here.
L404-L405: The mention of the five environments is redundant. They have been
mentioned before. I suggest deleting them.
L409: Please homogenize the spelling of “winter-storm” vs “winter storm” in the text.
L472: I suggest replacing “asl” with “above sea level” or defining “asl”.
L78: I suggest replacing “altitude” with “elevation”. While altitude is the height above
ground, elevation is the height above sea level.
L491: I suggest replacing “damages” with “damage” because it is an uncountable noun in
this context.
L497, Figure 2: Please replace “usefull” with “useful” in the figure legend.
L503: Please provide more information on the critical wind speed. Is this the
instantaneous wind speed as sum of mean wind speed and gust speed or is this the mean
wind speed alone? If so, what is the averaging interval for CWS?
L510: The maximum bending moment at the stem base is also strongly dependent on the
crown architecture and dimensions. Trees with large crowns dissipate large amounts of
energy in the crown space before any moment can be measured at the stem base.
L519: Please define the abbreviation “DBH”.
L525: Please define the abbreviation “NDVI”.
L529: Please replace “drag coefficient” with “mean drag coefficient”. The instantaneous
drag coefficient of trees under wind loading is still largely unknown because it varies
instantaneously.
L548: Here, you use “diameter of breast height” instead of “DBH”. It would better to
consistently used either the long name or the abbreviation.
L551: Here, you use “Critical wind speed”. It would better to consistently used either the
long name or the abbreviation.
L552-L553: Please correct the formatting of the citation.
L555-L564: How are these lines connected to wind-forest interactions? I suggest moving
these lines into a more general statements section or deleting them.
L566: I suggest replacing “Urban” with “Urban areas”. “Urban” is unspecific.
P15, section 4.3.:
- Why are the subsections not numbered? In the previous sections, the subsections were
numbered.
- There is an inconsistency in the headings of the subsections. The heading of the first
subsection in 4.2. was “4.2.1 Topographic indices” (à 4.2.2 Topographic indices). In this
section, it is “The urban boundary layer”. I suggest, adding a section something like
“4.1.2. The forest boundary layer”. This would strengthen the structure of the manuscript.
Topographic indices are of a totally different quality when it comes to the assessment of
“The small-scale interactions …” (L568), in forest and urban areas.
L594-L598: Please replace “damages” with “damage”. This is an uncountable noun in this
context.
L608: What is the difference between “topographic index” and “orography index”? I guess,
there is none. I nonetheless suggest homogenizing these technical terms. More
semasiologically correct would probably the use of “terrain index”.
L611: Does “critical wind speed thresholds” correspond to “CWS”? If not, this should be
made clear.
L621-L622: Before, it was stated that gust speed is the most essential factor for storm
damage. Here, it is stated that the “maximum daily wind speed” is most influential. Is
gust speed equivalent to maximum daily wind speed? If not, what is the difference? What
is the period of maximum daily wind speed? Please clarify.
L645: Please replace “;” with “:”.
L645-L652: Please match the variables and their definitions listed in Table 2 with variables
mentioned elsewhere in the text. Otherwise, provide clearly distinctive definitions. For
example: Does vcrit correspond to CWS? If so, does CWS have a daily resolution? In the
text, you mentioned “maximum daily wind speed”. Does it correspond to vmax, being the
abbreviation for maximum daily gust speed? What is the definition of gust in this context?
L734: The agricultural sector is a crucial sector worldwide, not only in Europe.
L769-L778: I suggest deleting all information on climate indices that is not relevant for
this review.
L780: This section is also subdivided into subsection without numbering. Please
homogenize the numbering throughout the entire text.
L792: What kind of wind speed is mentioned here? Are these mean or instantaneous wind
speed values? Please clarify.
L793: Of what kind are the mentioned “critical threshold values”? Do they correspond to
CWS or vcrit or are they something different? Please clarify.
L805: Please check the citation formatting.
P22L823: Is suggest deleting “extreme wind events”. Or do you mean something other
than storms? If so, please elaborate.
L824: What do you mean by “stability”? Do you mean structural integrity? Please clarify.
L824-L826: What are “small-scale variations” in the wind field? Does this expression relate
to the spatial wind speed pattern? Or does it also address the temporal wind field
variability? Can “small-scale” be quantified? It does not sound to impact wind turbines a
lot.
L828-L834: Please rephrase these lines completely. The sequence of the contents is not
stringent.
L836: What is the meaning of “strong wind events” in this context? Does this refer to
productive or destructive wind events? If it refers to productive wind events, then these
events are an important part of the wind climate and should not be mentioned in this
review.
L836-L843: How are these lines connected to the article’s title? This is a list of wind
indices that are related to wind turbine site assessment.
L849: I suggest replacing “high-impact” in this context. High-impact or severe weather is
normally weather that causes wide-spread damage. What could possibly be the “positive
effect on wind energy production”? During high-impact weather wind turbines are shut
down and the production rapidly decreases to zero.
L867-L873: The definition of “compound event” is unclear. Can a compound event be
related to a single hazard? If so, this should be made clear.
L886: Please replace “Temperature” with the technically correct term “Air temperature”.
You mention “freezing of soil” which is directly related to “soil temperature”.
L897-L904: Your argument in these lines is not stringent. The statement “The impact of
wind on drought is relatively small.” cannot be backed by the statement “Wind is only
included in some drought indices through evapotranspiration …” This is not logical. This is
a methodical aspect of wind impact assessment.
L936-P26L968: Why is only DWD mentioned here given the large number of national
meteorological services? Given the scope of this review, it would be good to have more
information from other weather services in the text as well.
L938-L940: More information about “some cases” would be useful. For example, how
many and which weather services warn?
L942-L943: Previously, it was mentioned that the review was carried out for “five
environments”. Here, it is stated that threshold values were collected for “five sectors”
and “five environments”. The two expressions have different quality and scope. Which
expression is correct? The correct expression should consistently be used throughout the
text.
L946: Here, the definitions for WL classes are provided. I suggest providing them at the
beginning of the manuscript, in any case before L274.
L961: Please correct the formatting of “WL 1-4”. What kind of “speeds” do you mean?
Mean or instantaneous wind speed values? Please clarify.
L962-L968:
- Is it correct that “wind speed” and “gust speed” values are compared in this figure?
What is the importance of this comparison?
- Do the gust speed values correspond to 3 s values?
- What is the averaging interval of “mean wind”? Is the averaging interval for all displayed
values the same?
- Is “mean wind” equivalent to “mean wind speed”?
- Is the y-axis label “Wind speed” representative for all variables displayed in the figure?
- In the figure the information “Wind in hub height” is provided. Does this correspond to
“Wind speed in hub height”? In the figure caption “wind speed measured at the height of
the wind turbines” is mentioned. Is this the same quantity? Please clarify.
- I suggest replacing “Critical thresholds” with “Critical threshold ranges”. This seems to
be shown by this figure.
L972: Please uppercase “central Europe”.
L997-L1007: Please specify “indices” at every occurrence. Which indices do you mean?
Wind indices? Storm indices? Storm damage indices?
L1004: Please define the abbreviations R² and AUC.
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  • Sep 2020
  • ENERG CONVERS MANAGE
An important aspect of planning the future expansion of wind energy is the consideration of changes in available wind resources due to climate change. In previous studies simulations of the future behavior of wind resources were derived from regional climate models at coarse spatial resolutions not suitable for wind energy potential assessment at the wind turbine scale. Thus, this study investigates the hypothesis that changes in future wind resources initiated by climate change will influence important aspects of small-scale wind resource assessment. A new approach is introduced that can be used to quantify the (1) spatial wind resource availability, (2) temporal wind resource availability, and (3) geographical complementarity under climate change at the wind turbine scale. The assessment of the future spatiotemporal variations in wind resources is based on an ensemble of near-surface (10 m) wind speed time series at a daily resolution for the period 1981-2099 from 35 different regional climate models. Using the highly resolved (horizontal resolution: 200 m × 200 m) Wind Speed-Wind Shear model, the near-surface wind speed time series were bias-corrected and extrapolated to a wind turbine hub height of 140 m at the sites of the current wind turbines in Germany. Bias correction was carried out by matching the quantile distributions from the regional climate models and the Wind Speed-Wind Shear model. Afterward, a power curve of a modern 3.45 MW wind turbine was applied to calculate daily capacity factors. The results indicate small long-term changes in the wind resource availability under the representative concentration pathways 4.5 and 8.5. It was found, that the influence of the interannual variability of the German wind resource exceeds the influence of climate change on the wind resource. The newly developed approach goes beyond previous wind resource assessments under climate change because it offers the opportunity for the spatially explicit investigation of different aspects of wind resource assessment which allows to develop more sophisticated wind energy expansion plans. Although the results are valid only for the study area, the proposed methodology is portable to any other region around the world.
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