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I'm part of a project creating a public atlas to document and map people's subjective experiences of extreme weather events. I've included information and a link to a short survey below. Feel free to fill this out yourself, and/or forward to your networks via email, social media, etc. Thanks!
Extreme Weather Events Survey
Ecologies of Harm: Mapping Contexts of Vulnerability in the Time of Covid-19 The University of British Columbia
This is a digital commons project intended to provide equitable access to knowledge.
COVID-19 presents the potential for people and groups to become exposed to harm in new ways. To see the overlapping ways in which these harms may be occurring, we’ve designed a survey for experiences of extreme weather events that are affecting people across the world.
This is a citizen / community observation survey, open to anyone 18 years of age and older who wishes to contribute. Your descriptions will upload directly to an interactive map of the world that is publicly accessible on this website: https://blogs.ubc.ca/ecologiesofharmproject
Your participation is entirely voluntary, and you do not have to answer every question. If you do wish to participate, you do not need to record your name. You may contribute as many observations as you like!
Please share widely, and keep in mind that re-posting, “liking,” or “following,” will be visible to others on public network platforms.
Link to survey: https://arcg.is/fvO4G0
Principal Investigator: Dr. Leslie Robertson
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indeed very interesting
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I wanted to ask that if we have to develop a modelling tool to anticipate the impacts of weather extreme events on the water quality of a lake but the amount of information collected in the field is scarce. What kind of models would be better to use and which are the natural processes we should include in the models. Please guide me briefly if possible.
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I think mike she will be best suited for integrated hydro metrological and water quality modelling purpose
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Hello everyone
I would compute Hosking & Wallis discordancy test based on L-comoments for multivariate Regional Frequency Analysis. Please help me by answer to these questions.
1- Is that the same transpose of the U matrix in the attached file?
2- Are there any R packages related to multivariate L-comoments homogeneity tests?
I worked with “lmomco” and “lmomRFA” before this.
Thanks for any help.
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Dear Muhammad A. El Hameedy I am very thankful to you for your answers to my questions.
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Ecosystem service is widely recognized modelling approach for various environmental friendly practical-use.
Water can be accumulated in natural aquifers - lakes, wetlands, and anthropogenic reservoirs - (wet as well as dry) detention ponds. Retention of water in soil may be considered as the strategy aiming at slowing down extreme event in the urban area which implies Urban Heat Effect. Water retention may mitigate water scarcity, and enhance the water storage in cities, important for green-blue infrastructure.
It shall be a good idea to use soil water retention capacity as ecosystem service in urban area?
What do you think? I wonder wether it is possible, and if so, by which means to clearly distinguish the criterion for overall natural water retention measure, and soil and water conservation?
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In urban setup we have very less and sensetive ecosystems which provides a notable ecosystem services, which need to be restored to avail it services in future, as we have seen most degradation in these types of ecosystems in urban set up which in one way or the other disrupt provisioning/supporting/ regulatory/cultural services to the urban resident.
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Extreme precipitation may alter the mean diurnal cycle of precipitation for a specific region. How it can be handled while computing diurnal cycle? Any suggestion would be highly appreciated.
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Thanks Harry Haupt for your views. Actually, these are two ways to do the analysis which is perfectly alright. Apart from that I want to know what is the impact of extreme events on diurnal cycle based on previous research works.
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What do you think about the onset of extreme rainfalls in UAE. Is there any negative impact of excessive "cloud seeding" during 2019 (185 times)
Cloud seeding: is a type of weather modification that aims to change the amount or type of precipitation that falls from clouds by dispersing substances into the air that serve as cloud condensation or ice nuclei, which alter the microphysical processes within the cloud.
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I think we should pay more attention to the solar cycle and sunspots now that we have increased rainfall
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Dear Colleagues,
I want to model glass facades by ABAQUS under extreme events. For this simulation, I need the material characterization of glass facades. I would be immensely grateful if you guide me in this regard. I really appreciate you for your help in advance.
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Many thanks for your correction, dear Franz Nikolaus Pölzl .
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I wanted to observe the rotational velocity of the Hurricane which was reported to be around 175mph, but when I looked at reanlysis products like ERA Interim or 20CRV2C the maximum wind speed I can get is about 45mph, why is the speed in the reanalysis products so low. Or is just that they are measuring different speeds?
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Your question header says the speed is about 45 m/s (which is about 100 mph), but the question itself says 45 mph. Which is correct?
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I am trying to do a bi-variate (average intensity and duration) frequency analysis of extreme rainfall events for urban flood studies. I have hourly rainfall data for 45 years and have delinted into events using IETD. However, i am finding difficulty in selecting rainfall intensity threshold above which the events are considered to be extreme events. Some studies have used annual maximum average intensity, maximum depth, peak intensity, annual maximum cumulative probability etc. But, i would prefer a peak over threshold approach than annual maximum and of-course i can identify an appropriate threshold for average intensity (which is one of the bi-variate) using mean residual life plot. But using that method i am ending up with around 500 events, which i feel is too many to be treated as extremes. Could someone help me with this.
Thank you
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You may want to look at a technique called SiZer.
Rondonotti V, Marron JS, Park C. 2007. SiZer for time series: a new approach to the analysis of trends. Electron J Stat. 1:268–289.
Sonderegger DL, Wang H, Clements WH, Noon BR. 2009. Using SiZer to detect thresholds in ecological data. Front Ecol Environ. 7(4):190–195.
Zhang JT, Marron JS. 2005. SiZer for smoothing splines. Computation Stat. 20:481–502.
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Is there database or data platform can give completely the historical extreme events, and it is better for collecting much losses or mortality caused by the extreme event.
Thank you.
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EM-DAT see https://emdat.be/ run by the Centre for Research on the Epidemiology of Disasters at the School of Public Health at the Université catholique de Louvain in Belgium provides a global disaster database for both "natural" and "man-made" events. In addition to providing information on the human impact of disasters (e.g. the number of people killed, injured or affected) EM-DAT also provides disaster-related economic damage estimates and disaster-specific international aid contributions.
For floods the Dartmouth Flood Observatory (see http://floodobservatory.colorado.edu/) provides an archive of global flood events and their impacts dating back to 1985.
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Dear Researchers,
I would like to ask that Please guide me by sharing your knowledge and expert opinion "Which is the good tool for Extreme Climate Indices Analysis".
Kind Regards
Naveed.
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RClimdex as suggested by Sania is useful for this work
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We would like to invite you to contribute with your original research articles, reviews, and technical notes to the Special Issue "Climate prediction of extreme events" in the journal Geosciences.
More information can be found at:
Deadline for manuscript submissions: 31 August 2019
We are looking forward to your valuable contribution,
Dr. Marco Turco
Dr. Sonia Jerez
Guest Editors
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Certainly climate predictions do not allow forecasting the specific location/day an extreme event will occur. However they can inform about the probability of occurrence of climatic anomalies for the next months and seasons based on dynamical or empirical models. For instance, climate predictions provide probabilistic information about whether next season will be more, equal or less warm and/or humid than usual.
Traditionally these forecast systems provide monthly anomalies. However, forecasting statistics of extreme events, such as the number of frost/hot days within a season, can be more useful for industries and end-users due to their potential for damaging. In spite of the increasing interest in estimating the ability of forecast systems to predict extreme events, little work has been performed so far on the topic.
We hope that this special issue will provide new insight into this strategic issue.
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Dear all. It is known, that climate change and also extreme weather can cause outbreak of some pests and their enemies also. Other pests may be diminshed. The question is: How extreme weather events like heat, drought, storm, heavy down poors, hail, flooding will influence the special diseases of meadow fescue and the special plant protection measures (chemical and biological) in meadow fescue. We found nothing in literature but need more information for risk assessment. Under current climate conditions plant diseases and pests, (mammalians, weeds, insect pests, nematodes and plant pathogens like fungi, viruses, bacteria) can cause considerably yield losses and damages of crops. Climate change will likely lead to increase the frequency, intensity, spatial extent, duration and timing of weather and climate extremes. Does anyone have any information about the impacts of extreme weather events on diseases and pests of meadow fescue? We reviewed the possible impacts of weather extremes on pests (weeds, insect pests and plant pathogens) of meadow fescue by analyzing scientific literature published since 1945, concerning the knowledge about the influences of extreme weather on incidence of these pests.
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Dear Seidal,
As you know from your searches, a limited amount of information on the potential impacts of climate change on plant harmful organisms is available. It is known that extreme changes of climate affect plants in natural and agroecological conditions throughout the world. These changes directly impact plants and their interactions with harmful organisms. In addition, there is clear evidence that climate change is altering the distribution of plant harmful organisms, but the full effects are difficult to predict and need to be assessed on a case by case basis. From my point of view, extreme climate changes will affect pests, yield and quality of meadow fescue. The prediction is that extraordinary weather conditions may alter rates of pest development, affect host resistance and lead to changes in the physiology of host - pest interactions of meadow fescue. However, can’t say that how much this conversion will realize. It needs to be studied.
Good luck
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Dear Researchers,
Please, let me know which is the best Statistical Downscaling Technique for Precipitations and Temperatures. I have to use 20 GCMs data. If anybody have developed own code using MATLAB, R or any language. Please also comment.
Thanks in advance.
Regards
Naveed Ahmed
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Hello,
It's hard to say which is the best statistical down-scaling technique. There are no globally accepted technique available. Depending on your purpose and availability of data you can select the tool or compare different tools for your region and select.
Some useful references
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I have discharge data for 2007-2017. I want to do frequency analysis to calculate extreme event. In which process should I do it?? and is there any excel file to calculate?
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Dear Gazi,
You can find step-wise and easy-to-follow procedure for low flow frequency analysis demonstrated in the first paper (see first link).
In another study (see link for the second paper), low frequency analysis was done using discharge data from 24 catchments in the Lake Victoria basin in the paper below. How to quantify uncertainty in sampling of low flow events is also explained.
On how to model the amplitude-duration-frequency relationships for low flow, the third paper might be relevant for you case.
Deleted research item The research item mentioned here has been deleted
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Since, extreme events are the rare events with in the climate cycle, is a modeling framework based study reliable for analyzing the changes in extreme events and their interactions with the components of the earth system, or we have to depend on an observation based systems for extreme event studies. 
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One thing that would be sensible to do is to use multiple climate models to get an idea of the range of projections of drought /precipitation changes.
For example, you could look at the same drought index in 
  1. all of the CMIP5 models projections
  2. all of the CMIP5 models twentieth-century simulations
  3. the CORDEX output for India region
  4. all recent observations
This would give you an idea of how good the climate models are, and also the spread of projections over the next century.  I don't know whether this has already been done though; you would need to search the literature.
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Dear Experts,
I am working on a project around extreme events. I would like to know what are some of the common cognitive reactions that are usually studied in the field of organizational behavior (e.g., self-efficacy, organizational based self esteem)? 
Thank you.
Regards,
Sheldon. 
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Thank you Gregoire for your reply. This was indeed helpful.
Regards,
Sheldon. 
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A depression over Central India may seem the reason behind the heavy precipitation. But is there any connection of climate change and global warming on flood conditions there.
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Dear Annu,
Yesterday I ran through the entire 2007-2016 http://rammb.cira.colostate.edu/products/tc_realtime/ archive for evert "North Indian Ocean" storm located in their "Real-Time Tropical Cyclone Products", and then within each storm, about half way down through all of the different image modes, click on "Storm Relative 16 km Geostationary Water Vapor Imagery" on the "Archive" link.
Once there, scroll to the bottom and click on the last "Display Loop" button to watch the battle between the Pakistan-Arabia Dust Cloud and the most powerful monsoon forces, the cyclones--and the cyclones ALWAY lose.  
Every single cyclone, even the Category-Fives do not have any power if they are located east or west of India, to get past the Dust Cloud. GONU, SIDR,  PHET, LAILA, JEILA, MADI, HELEN, NILOFAR, CHAPALA, ROANU---you can carve on the tombstones of each of these cyclones, "KILLED BY THE DUST CLOUD".
Then we need to look at the host plant sources of the Pseudomonas bacteria, that actually create the monsoon rain clouds each year, and they always make very distinctive cloud patterns that you can see from space, and then track their sources back to the small grove of native trees that are the host plants. 
I have attached a few of the cyclone-Dust Cloud battle images, and yesterday's Pseudomonas cloud image plus a satellite vegetation cover for India from Google Earth. I have downloaded these images to use them for paintings on canvas I am going to post at http://www.ecoseeds.com/art.html.  
I hope this information is helpful.  I have been studying these monsoon-Dust Cloud interactions for 14 years now.
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I am working on hydro logical extreme events under hypothetical climate change. but  i refer some studies about hypothetical climate scenarios  and pointed out different range of hypothetical climate scenarios with out any reasons would any one help me how to build a hypothetical climate scenarios  or reasonable references?   
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I am working with extreme temperature events. To accomplish my work I have to define extreme temperature threshold (maximum and minimum). More explicitly,  after which temperature I call it extreme (for both maximum and minimum) for my data. Is there any standard process to establish threshold value based available data?
Thanks in advance.
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Dear Sheikh,
In your series and as far as I could understand your, question the problem is to eliminate too extreme values (the outliers) in order to determine a max and a min.  The usual (non parametric) way do do that is to consider that some values are outside a certain range. This range is function of the upper or lower quartile of your series. In the formulae I gave you, this is expressed by the difference of the upper quartile minus the first quartile multiplied by alpha, an empirical parameter.
You can use other methods for the detection of outliers: the Dixon's test for small series (less than 10 members), or the Grubbs'  test, but they are parametric tests and you must first check that your series has a normal distribution.
If you use Fortran I can provide you a program for that. Contact me by email
G.C.
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I want to evaluate extreme events in a basin specially perennial rivers , African Rivers Case  i try to use the statistical methods of extreme analysis like the POT and general Pareto methods. but the main challenge face to me is that how can I select the specific thresholds  to evaluate with out  a given depth of flow that results in a flood or a drought? How can i define the thresholds, based on the data i have?  If you look at the observed runoff for one of  stations in the  catchment, how will determine the times when there were extreme events? floods or drought? if any one know some methods please put here with some references,thank you
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Hi
I send you a work to which I participated in West Africa about extreme runoff detection and modelling.
I hope it helps you.
Best
Gil
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Hi,
I am looking for software to help regulators manage emergency response teams in case of extreme events of air pollution release or odor complaints from citizens.
The software should:
  1. be connected at real time to air quality and meteorological stations (and possibly air quality model outputs),
  2. be able to run backward/forward trajectories,  
  3. display location and time of complaints reported by citizens,
  4. provide information about the potential / suspected emission sources. 
One example I came across is Odournet's odourmap (www.odourmap.com).
Thanks,
Ilan
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hi Ilan, 
have you found a solution in the mean time ( I know your post is from 2014). However, if you are still looking for a good solution, please get in contact mit Christoph Mannebeck , the creator of Odourmap. His email is cmannebeck@olfasense.com. He will be able to answer all your questions and help you to find the best suitable solution for you. 
Best regards, Nathalie 
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This question has been around for decades and it requires truly interdisciplinary efforts to answer.
The major ecosystems of the planet are critically important for humans and for all creatures, and they are currently subject to very strong pressure from climate change and from human-induced ecological disturbances, such as agriculture and invasive species. Ecosystems change both slowly and abruptly in apparent response to extreme events that may be embedded in long-term change. Ecosystems have strong feedback effects on the atmospheric budgets of heat, moisture, greenhouse gases and aerosols, and, therefore, on climate.
To find out how climate change will affect forests and dry-land vegetation, and how those changes will affect atmospheric composition, we need more observations. Observations need to be on timescales of decades or longer to reflect processes in the atmosphere and of the major ecosystems. They also need to span local, regional and global spatial scales. Finally, we need ecosystem models integrated with atmospheric models that work like real systems.
In the United States, there are efforts to study parts of this problem and to make the requisite observations, supported by the National Science Foundation, the Department of Energy, NASA, the U.S. Forest Service and NOAA. What remains to be done is to coordinate and invigorate these efforts, and to commit to solving the problem on the relevant time and space scales. We have certainly seen a lot of progress in the last few years, but it has mostly served to point to the serious the gaps in our knowledge.
Ecosystem health goes hand-in-hand with human health and economic vitality. Atmosphere-biosphere interactions are powerful and have vast implications.   
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I can anticipate the results of a personal research on forests.
The main forest associations were well characterized by Sandro Pignatti in his book on “Boschi d’Italia” (1998), giving the possibility to calculate the biotic indices of Ellenberg at the moment of their first relevés. These data can be compared with the Ellenberg indices of recent forest surveys (2005-2015). In this period of about 50-60 years, the raise of climatic temperature was strong: after 1985 the mean T°C increased in Italy of about 1-2 °C and the perennial snow limit of altitude on the Alps passed from 2980 to 3080 m.
            The analysis of 72 forest samples indicate two different behaviours, (1) the boreal-Alpine conifer formations present a little decrease in thermophile species, while (2) the temperate and Mediterranean formations increased their thermophile species. So, even altitudinal belts follow a similar behaviour. Anyway, at this time the increase of thermophile species (case 2) results 7.47% in an altitude belt of 180 m (mean), while the decrease (case 1) results 3.0 % in an altitude belt of 1520 m (mean).
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For example, in hydrology, for a monthly flow series, how can I determine the possibility that one point indicates an extreme high (or low) flow event, and the duration of that event?
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One-point extreme events are often handled with extreme events distributions or outlier analyais. In case of, let's say, "extreme periods" (i.e. more than one extreme value close to the other) as it seams since you are considering duration, you probably should consider the change-point detection analysis. This approach is not that popular even if it is widely applied in the homogeneity assessment and in the homogenization procedures adopted in climatology.
A broade literature exists on this topic. To have a look on the part concerning climate go to: www.homogenisation.org , the site provides a nearly complete list of papers on the topic (theory, applications and so forth). Obviously the same techniques adopted in climatology can be applied to other tipes of data series, provided that they comply the conditions the specific method is suited to handle.
Best wishes
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Maybe something like flood events for heavy snowfalls.
Any idea/publication/link!
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Dear @Rogerio @Jan @Fulvio,
Thanks for your input and useful documents.
@Rogerio
Some notes!
To the "First Observation", what about FLOODS?
The floods are also is a type of river flow.
While we design the large dams and risk of several water engineering projects based on the flood return period (Let say instantaneous peak discharge).
To the "Second Observation",
What we mean by "HEAVY SNOW", the heavy snow has higher water equivalent (you are right), but I want to focus on the damages caused by snow height in its solid form (as a hydrological component) or heavy snowfall (as an extreme hydrologic event).
Through the past week most cities of Iran from west to east have been blanketed under heavy snow which has crippled the residents. Northern Iran has been hit by its heaviest snowstorm in 60 years and faced the worst problems. The roofs of many houses and public facilities have collapsed under heavy snow.
The snow height/weight can be used as a measure by urban designer/architects to prevent/reduce undesirable consequences of extreme snowfall events. (Like Flood Return Period for Hydrologic Engineers)
May be a link between snow hydrology and disaster management to reduce the economic losses.
Just my point of view based on a little knowledge.