Dust Storm Forecasting for Al Udeid AB, Qatar: An Empirical Analysis

Dust storms are extreme weather events that have strong winds laden with visibility reducing and operations limiting dust, The Central Command Air Forces (CENTAF) 28th Operational Weather Squadron (OWS) is ultimately responsible for forecasting weather in the vast, data denied region of Southwest Asia in support of daily military and humanitarian operations. As a result, the 28th OWS requests a simplified forecasting tool to help predict mesoscale dust events that affect coalition operations at Al Udeid AB, Qatar. This research satisfies the 28th OWS request through an extensive statistical analysis of observational data depicting seasonal dust events over the past 2 years. The resultant multiple linear regression best fit model combines 28 easily attainable model outputs, satellite imagery, surface and upper air observations, and applies a linear transformation equation. The best fit model derived provides the end user with a numerical visibility prediction tool for Al Udeid AB that is verified against a seasonally divided and independent validation data set that yields an R2 of 0.79 while maintaining \u3c 800 m accuracy

A Computational Tool for Evaluating THz Imaging Performance in Brownout Conditions at Land Sites throughout the World

This study quantifies terahertz (THz) or sub-millimeter imaging performance during simulated rotary-wing brownout or whiteout environments based on geographic location and recent/current atmospheric weather conditions. The atmospheric conditions are defined through the Air Force Institute of Technology Center for Directed Energy (AFIT/CDE) Laser Environmental Effects Definition and Reference or LEEDR model. This model enables the creation of vertical profiles of temperature, pressure, water vapor content, optical turbulence, and atmospheric particulates and hydrometeors as they relate to line-by-line layer extinction coefficient magnitude at wavelengths from the UV to the RF. Optical properties and realistic particle size distributions for the brownout and whiteout particulates have been developed for and incorporated into LEEDR for this study. The expected imaging performance is assessed primarily at a wavelength of 454 μm (0.66 THz) in brownout conditions at selected geographically diverse land sites throughout the world. Seasonal and boundary layer variations (summer and winter) and time of day variations for a range of relative humidity percentile conditions are considered to determine optimum employment techniques to exploit or defeat the environmental conditions. Each atmospheric particulate/hydrometeor is evaluated based on its wavelength-dependent forward and off-axis scattering characteristics and absorption effects on the imaging environment. In addition to realistic vertical profiles of molecular and aerosol absorption and scattering, correlated optical turbulence profiles in probabilistic (percentile) format are used

Investigations of Desert Dust and Smoke in the North Atlantic in Support of the TOMS Instrument

During the initial period of the work we concentrated on Saharan dust storms and published a sequence of papers (Colarco et a1 2002,2003a,b, Toon, 2004). The U.S. Air Force liked the dust model so well that they appropriated it for operational dust storm forecasting (Barnum et al., 2004). The Air Force has used it for about 5 yrs in the Middle East where dust storms cause significant operational problems. The student working on this project, Peter Colarco, has graduated and is now a civil servant at Goddard where he continues to interact with the TOMS team. This work helped constrain the optical properties of dust at TOMS wavelengths, which is useful for climate simulations and for TOMS retrievals of dust properties such as optical depth. We also used TOMS data to constrain the sources of dust in Africa and the Middle East, to determine the actual paths taken by Saharan dust storms, to learn more about the mechanics of variations in the optical depths, and to learn more about the mechanisms controlling the altitudes of the dust. During the last two years we have been working on smoke from fires. Black carbon aerosols are one of the leading factors in radiative forcing. The US Climate Change Science Program calls this area out for specific study. It has been suggested by Jim Hansen, and Mark Jacobsen among others, that by controlling emissions of black carbon we might reduce greenhouse radiative forcing in a relatively painless manner. However, we need a greatly improved understanding of the amount of black carbon in the atmosphere, where it is located, where it comes from, how it is mixed with other particles, what its actual optical properties are, and how it evolves. In order to learn about these issues we are using a numerical model of smoke. We have applied this model to the SAFARI field program data, and used the TOMS satellite observations in that period (Sept. 2000). Our goal is to constrain source function estimates for black carbon, and smoke optical properties

Trajectory Calculation as Forecasting Support Tool for Dust Storms

In arid and semiarid regions, dust storms are common during windy seasons. Strong wind can blow loose sand from the dry surface. The rising sand and dust is then transported to other places depending on the wind conditions (speed and direction) at different levels of the atmosphere. Considering dust as a moving object in space and time, trajectory calculation then can be used to determine the path it will follow. Trajectory calculation is used as a forecast supporting tool for both operational and research activities. Predefined dust sources can be identified and the trajectories can be precalculated from the Numerical Weather Prediction (NWP) forecast. In case of long distance transported dust, the tool should allow the operational forecaster to perform online trajectory calculation. This paper presents a case study for using trajectory calculation based on NWP models as a forecast supporting tool in Oman Meteorological Service during some dust storm events. Case study validation results showed a good agreement between the calculated trajectories and the real transport path of the dust storms and hence trajectory calculation can be used at operational centers for warning purposes

Prediction of dust storms in construction projects using intelligent artificial neural network technology

Sandstorms (dust storms) are considered the most events which cause destructive and costly damages in lots of desert regions. These sandstorms may be a reason of huge disasters (damages) on Environmental as well as Health aspects. The aim of this paper is to develop a mathematical model for predicting the Dust Storm in Republic of Iraq using Artificial Neural Network (ANN) technique. As a case study, four construction projects in Iraqi cities were selected (Baghdad, Basrah, Samawa, and Nasiriya) in order to identifying and prediction of the sandstorms, which significantly help to reduce the effects of damages. Only one ANN model was built to predict a dust storm. The datas of this model cited from Iraqi Meteorological Organization and Seismology. Four factors were adapted to develop the model (Max. Temperature, Min. Temperature, Rain and Wind), It was found that ANN has the ability to predict the dust storm with a high accuracys off the correlation coefficient (R) which is 90.00%, with a percentage of average accuracy is 89%

Spatial and temporal variations in the incidence of dust storms in Saudi Arabia revealed from in situ observations

This is the final version. Available from the publisher via the DOI in this record.Monthly meteorological data from 27 observation stations provided by the Presidency of Meteorology and Environment (PME) of Saudi Arabia were used to analyze the spatial and temporal distribution of atmospheric dust in Saudi Arabia between 2000 and 2016. These data were used to analyze the effects of environmental forcing on the occurrence of dust storms across Saudi Arabia by considering the relationships between dust storm frequency and temperature, precipitation, and wind variables. We reveal a clear seasonality in the reported incidence of dust storms, with the highest frequency of events during the spring. Our results show significant positive relationships (p < 0.005) between dust storm occurrence and wind speed, wind direction, and precipitation. However, we did not detect a significant relationship with temperature. Our results reveal important spatial patterns, as well as seasonal and inter-annual variations, in the occurrence of dust storms in Saudi Arabia. For instance, the eastern part of the study area experienced an increase in dust storm events over time, especially in the region near Al-Ahsa. Similarly, an increasing trend in dust storms was also observed in the west of the study area near Jeddah. However, the occurrence of dust storm events is decreasing over time in the north, in areas such as Hail and Qaisumah. Overall, the eastern part of Saudi Arabia experiences the highest number of dust storms per year (i.e., 10 to 60 events), followed by the northern region, with the south and the west having fewer dust storm events (i.e., five to 15 events per year). In addition, our results showed that the wind speeds during a dust storm are 15-20 m/s and above, while, on a non-dust day, the wind speeds are approximately 10-15 m/s or lower. Findings of this study provide insight into the relationship between environmental conditions and dust storm occurrence across Saudi Arabia, and a basis for future research into the drivers behind these observed spatio-temporal trends

Environmental Factors that Influence the Geography of Yemen Leading to Dust and Sand Storms - A Case Study

In Yemen, the dust storm is a common phenomenon severely affecting the economy and health. Yemen is located in a semi-desert desert area, where dust and sand storms occur all year round, however they are the most common at summer (from June until the end of September). Coastal areas (Hajjah, Hoddeidah, Taiz, Lahg, Aden, Abyan, Shabwah and Hadramout) and desert areas (Marib and Al Jowf) are affected by dust and sandstorms almost all year round. The western and central governorates of Yemen are mountainous regions, but influenced by dust too. Dust storms in Yemen have an impact on humans, animals, plants and all environmental ecosystems. In this article, we attempted to understand the possible relationship between environmental parameters such as wind temperature, and precipitation, which influence the development of dust and sand storms in and around Yemen. Statistical analysis such as descriptive statistics, T-test, ANOVA one-way test, Tukey test, Levene test, and Correlation test were performed. The statistical analysis confirms that there is a significant correlation between wind, temperature and precipitation at 0.01 and 0.05 levels. The results further depict that environmental factors play a vital role in the formation of dust and sand storm. The results obtained are encouraging and further research will be conducted based on technological evidence

Spatial and temporal variations in the incidence of dust storms in Saudi Arabia revealed from in situ observations

Monthly meteorological data from 27 observation stations provided by the Presidency of Meteorology and Environment (PME) of Saudi Arabia were used to analyze the spatial and temporal distribution of atmospheric dust in Saudi Arabia between 2000 and 2016. These data were used to analyze the effects of environmental forcing on the occurrence of dust storms across Saudi Arabia by considering the relationships between dust storm frequency and temperature, precipitation, and wind variables. We reveal a clear seasonality in the reported incidence of dust storms, with the highest frequency of events during the spring. Our results show significant positive relationships (p < 0.005) between dust storm occurrence and wind speed, wind direction, and precipitation. However, we did not detect a significant relationship with temperature. Our results reveal important spatial patterns, as well as seasonal and inter-annual variations, in the occurrence of dust storms in Saudi Arabia. For instance, the eastern part of the study area experienced an increase in dust storm events over time, especially in the region near Al-Ahsa. Similarly, an increasing trend in dust storms was also observed in the west of the study area near Jeddah. However, the occurrence of dust storm events is decreasing over time in the north, in areas such as Hail and Qaisumah. Overall, the eastern part of Saudi Arabia experiences the highest number of dust storms per year (i.e., 10 to 60 events), followed by the northern region, with the south and the west having fewer dust storm events (i.e., five to 15 events per year). In addition, our results showed that the wind speeds during a dust storm are 15–20 m/s and above, while, on a non-dust day, the wind speeds are approximately 10–15 m/s or lower. Findings of this study provide insight into the relationship between environmental conditions and dust storm occurrence across Saudi Arabia, and a basis for future research into the drivers behind these observed spatio-temporal trends

Environmental factors that influence the geography of Yemen leading to dust and sand storms - a case study

In Yemen, the dust storm is a common phenomenon severely affecting the economy and health. Yemen is located in a semi-desert desert area, where dust and sand storms occur all year round, however they are the most common at summer (from June until the end of September). Coastal areas (Hajjah, Hoddeidah, Taiz, Lahg, Aden, Abyan, Shabwah and Hadramout) and desert areas (Marib and Al Jowf) are affected by dust and sandstorms almost all year round. The western and central governorates of Yemen are mountainous regions, but influenced by dust too. Dust storms in Yemen have an impact on humans, animals, plants and all environmental ecosystems. In this article, we attempted to understand the possible relationship between environmental parameters such as wind temperature, and precipitation, which influence the development of dust and sand storms in and around Yemen. Statistical analysis such as descriptive statistics, T-test, ANOVA one-way test, Tukey test, Levene test, and Correlation test were performed. The statistical analysis confirms that there is a significant correlation between wind, temperature and precipitation at 0.01 and 0.05 levels. The results further depict that environmental factors play a vital role in the formation of dust and sand storm. The results obtained are encouraging and further research will be conducted based on technological evidence

Developing and testing a coupled regional modeling system for establishing an integrated modeling and observational framework for dust aerosol

To this date, estimates of the climate response to mineral dust remain largely uncertain because of our limited capability to quantify dust distribution in the atmosphere. Focusing on the Central and East Asian dust source regions, this thesis aims to develop a coupled regional dust modeling system to provide an improved modeling capability of atmospheric dust as well as to aid the integration of ground-based and satellite observations. The objectives of this study are as follows: 1) evaluate the capabilities of the available data to detect and quantify mineral dust in the atmosphere; 2) develop and test a coupled regional dust modeling system able to simulate size resolved dust concentrations accounting for the regional specifics of Central and East Asia; and 3) outline a methodology for data and modeling integration. The capabilities of ground-based and satellite data to characterize dust in the atmosphere are examined in great details. Based on analysis of MODIS data reflectance and radiances, we found evidence for regional signature of dust in near-IR and proposed a new probabilistic dust-cloud mask that explicitly takes into account the spatial variability characteristics of dust aerosols. We developed a coupled regional dust modeling system (WRF-DuMo) by incorporating a dust emission module (DuMo) into the NCAR WRF model. The WRF-DuMo unique capabilities include explicit treatment of land surface properties in Central and East Asia, a suite of dust emission schemes with different levels of complexity, multiple options for dust injection in the atmosphere and flexible parameters of the initial size distribution of emitted dust. Two representative dust events that originated in East Asia in the springs of 2001 and 2007 have been modeled with WRF-DuMo. Simulations with different initial size distribution of dust, injection and emission parameterizations have been performed to investigate their relative role on the modeled dust fields. We performed an integrated analysis of modeled dust fields and satellite observations by introducing an ensemble model dust index, which used in conjunction with satellite dust retrievals improves the capability to characterize dust fields. Finally, we provide recommendations for the development of an integrated observational and modeling dust framework.Ph.D.Committee Chair: Sokolik, Irina; Committee Member: Curry, Judith; Committee Member: Kalashnikova, Olga; Committee Member: Nenes, Athanasios; Committee Member: Stieglitz, Mar