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The global spatiotemporal pattern of mortality risk and burden attributable to tropical cyclones is unclear. We aimed to evaluate the global short-term mortality risk and burden associated with tropical cyclones from 1980 to 2019.

This dissertation contains three empirical studies on the impact of three distinct government policies, ranging from the provision of agricultural insurance in Mexico to improved pollution controls on school buses in California. All three papers take advantage of administrative data from the respective programs and use selection on unobservables designs to obtain causal estimates for the impacts of these programs. Chapter 1 estimates the impact of an index- based agricultural insurance offered to small-holder farmers by the Mexican government on their income and consumption following a negative weather shock, as well as investment decisions for the subsequent growing season. Chapter 2 analyzes how the nutritional quality of the meals provided through the National School Lunch Program (NSLP) affects students’ academic outcomes, as measured by standardized test scores. By studying the nutritional quality of these meals, as opposed to simply their availability, this analysis provides and important contribution to the body of literature on the educational benefits of the NSLP. In Chapter 3, I study the impact of the California Lower-Emission School Bus Program (LESBP), which seeks to lower the pollution emissions of school buses through replacements and retrofits, on students’ school attendance and standardized test scores.The first chapter of this dissertation, co-authored with Alain de Janvry and Elisabeth Sadoulet, examines the ex-post, shock-coping impact of weather index insurance from a pioneering, large-scale insurance program in Mexico to cover smallholder farmers as a social safety net. Exploiting insurance thresholds as a source of plausibly exogenous variation in insurance payments, we find evidence that these payments allow farmers to cultivate a larger land area in the growing season following a weather shock. Households in municipalities receiving payments also have larger per capita expenditures and income in the subsequent year. These results suggest tha

Whether on an urban or planetary scale, covering time scales of a few minutes or a few decades, the societal need for more accurate weather, climate, water, and environmental information has led to a more seamless thinking across disciplines and communities. This challenge, at the intersection of scientific research and society’s need, is among the most important scientific and technological challenges of our time. The “Science Summit on Seamless Research for Weather, Climate, Water, and Environment” organized by the World Meteorological Organization (WMO) in 2017, has brought together researchers from a variety of institutions for a cross-disciplinary exchange of knowledge and ideas relating to seamless Earth system science. The outcomes of the Science Summit, and the interactions it sparked, highlight the benefit of a seamless Earth system science approach. Such an approach has the potential to break down artificial barriers that may exist due to different observing systems, models, time and space scales, and compartments of the Earth system. In this context, the main future challenges for research infrastructures have been identified. A value cycle approach has been proposed to guide innovation in seamless Earth system prediction. The engagement of researchers, users, and stakeholders will be crucial for the successful development of a seamless Earth system science that meets the needs of society.

In this thesis, a novel framework has been developed to quantify the radiation from tropical cyclones (TCs) in shortwave (SW) and longwave (LW) portions of the optical spectrum. The framework includes two stages: segmentation of TC clouds and calculation of the radiation attenuation due to TC clouds. The segmentation task was accomplished by an algorithm which takes a time series of brightness temperature images of tropical cyclones and uses image processing techniques to acquire segmentation for each image. The radiation was calculated by combining the segmentations with a radiation dataset provided by the Cloud and Earth's Radiant Energy System dataset via a coordinate-matching scheme due to their difference in resolution. The framework was used to investigate some preliminary results as part of a hypothesis that links the radiation due to TC and climate change. The framework was successfully implemented to analyse TCs' radiation in 2016, at the regional and global scales. Results show that TCs contributed a total of 21.25 TW of radiation to the global upwelling radiation, which is attributable by 152.27 TW in reflected shortwave radiative contribution and 131.02 TW in the emitted longwave radiative reduction.Although the radiation contribution from TCs was confirmed to be of the right order of magnitude to affect the Earth's Energy Balance, its impact on the balance would depend on how much the contribution varies, observed throughout a sufficient period of time. While this inquiry would require another comprehensive research, the framework remains the main contribution of the thesis. The framework has laid an important foundation for future work on TC radiation in general and for further insights into the impacts of TCs on climate change in particular.

The extratropical transition (ET) of tropical cyclones often has an important impact on the nature and predictability of the midlatitude flow. This review synthesizes the current understanding of the dynamical and physical processes that govern this impact and highlights the relationship of downstream development during ET to highimpact weather, with a focus on downstreamregions. It updates a previous review from2003 and identifies new and emerging challenges and future research needs. First, the mechanisms through which the transitioning cyclone impacts the midlatitude flow in its immediate vicinity are discussed. This ‘‘direct impact’’manifests in the formation of a jet streak and the amplification of a ridge directly downstream of the cyclone. This initial flow modification triggers or amplifies amidlatitude Rossby wave packet,which disperses the impact ofETinto downstream regions (downstream impact) and may contribute to the formation of high-impact weather. Details are provided concerning the impact of ET on forecast uncertainty in downstream regions and on the impact of observations on forecast skill. The sources and characteristics of the following key features and processes thatmay determine the manifestation of the impact of ET on the midlatitude flow are discussed: the upper-tropospheric divergent outflow, mainly associated with latent heat release in the troposphere below, and the phasing between the transitioning cyclone and the midlatitude wave pattern. Improving the representation of diabatic processes during ET in models and a climatological assessment of the ET’s impact on downstream high-impact weather are examples for future research directions.

• Background Current multimodal approaches for the management of non-specific patellofemoral pain are not optimal, however, targeted intervention for subgroups could improve patient outcomes. This study explores whether subgrouping of non-specific patellofemoral pain patients, using a series of low cost simple clinical tests, is possible. • Method The exclusivity and clinical importance of potential subgroups was assessed by applying à priori test thresholds (1 SD) from seven clinical tests in a sample of adult patients with non-specific patellofemoral pain. Hierarchical clustering and latent profile analysis, were used to gain additional insights into subgroups using data from the same clinical tests. • Results One hundred and thirty participants were recruited, 127 had complete data: 84 (66%) female, mean age 26 years (SD 5.7) and mean BMI 25.4 (SD 5.83), median (IQR) time between onset of pain and assessment was 24 (7-60) months. Potential subgroups defined by the à priori test thresholds were not mutually exclusive and patients frequently fell into multiple subgroups. Using hierarchical clustering and latent profile analysis three subgroups were identified using 6 of the 7 clinical tests. These subgroups were given the following nomenclature: (i) ‘strong’, (ii) ‘weak and tighter’, and (iii) ‘weak and pronated foot’. • Conclusions We conclude that three subgroups of patellofemoral patients may exist based on the results of six clinical tests which are feasible to perform in routine clinical practice. Further research is needed to validate these findings in other datasets and, if supported by external validation, to see if targeted interventions for these subgroups improve patient outcomes.

Patellofemoral Pain (PFP) is a musculoskeletal disorder causing significant pain and dysfunction around the knee, commonly leading to long term limitations. People with PFP are commonly referred for physiotherapy, although current multimodal physiotherapy approaches tend to be rather ad-hoc and are failing in the long term. Identification of patient strata (or subgroups) who may respond differentially to interventions has been recognised as an international priority. It has been proposed that there are PFP patient strata, classified based on clinical tests, who would respond to modes of interventions targeted at the individual's stratum.

Calibrated, multiband radiometric measurements of the optical radiation emitted by rocket-triggered lightning (RTL) have been made in the ultraviolet (UV, 200-360 nm), the visible and near infrared (VNIR, 400-1000 nm), and the long wave infrared (LWIR, 8-12 µm) spectral bands. Measurements were recorded from a distance of 198 m at the University of Florida International Center for Lightning Research and Testing (ICLRT) during the summers of 2011 and 2012. The ICLRT provided time-correlated measurements of the current at the base of the RTL channels. Following the onset of a return stroke, the dominant mechanism for the initial rise of the UV and VNIR waveforms was the geometrical growth of the channel in the field-of-view of the sensors. The UV emissions peaked about 0.7 µs after the current peak, with a peak spectral power emitted by the source per unit length of channel of 10 ± 7 kW/(nm-m) in the UV. The VNIR emissions peaked 0.9 µs after the current peak, with a spectral power of at 7 ± 4 kW/(nm-m). The LWIR emissions peaked 30-50 µs after the current peak, and the mean peak spectral power was 940 ± 380 mW/(nm-m), a value that is about 4 orders of magnitude lower than the other spectral band emissions. In some returns strokes the LWIR peak coincides with a secondary maximum in the VNIR band that occurs during a steady decrease in channel current. Examples of the optical waveforms in each spectral band are shown as a function of time and are discussed in the context of the current measured at the channel base. Source power estimates in the VNIR band have a mean and standard deviation of 2.5 ± 2.2 MW/m and are in excellent agreement with similar estimates of the emission from natural subsequent strokes that remain in a pre-existing channel which have a mean and standard deviation of 2.3 ± 3.4 MW/m. The peak optical power emitted by RTL in the UV and VNIR bands are observed to be proportional to the square of the peak current at the channel base. The same trend was

Tropical cyclones (TCs) can make significant size changes during their lifetime. Being able to accurately forecast TC size change is important for predicting the onset of storm surge as well as the spatial extent of damaging winds. TC size changes can occur from internal storm dynamics, such as eyewall replacement cycle or from changes in the synoptic environment. In this study, the impacts of changing the atmospheric temperature and air-sea temperature difference on TC size and structure are investigated. The study is conducted in two parts: the first part uses the WRF-ARW model to test the sensitivity of TC size changes to simple changes in the environment; the second part to validates the results from the first part by characterizing the environments associated with real cases of TC size change in the North Atlantic basin. It is found that when the simulated atmosphere is cooled, the initial specific humidity and convective available potential energy (CAPE) decrease but the surface energy fluxes from the ocean increase. The higher surface fluxes produce a wider area of radially-inflowing air in the boundary layer, which supports a larger precipitation field and the formation of outer-core spiral rainbands. The larger precipitation field translates to a larger wind field, which is likely related to the diabatic production of potential vorticity. In contrast, when the atmosphere is warmed the surface energy fluxes reduce, which ultimately inhibits the growth of the TC wind field. The higher initial CAPE and moisture content, however, allow the TC to spin up more rapidly with a compact core of intense precipitation. Thus, it is not the temperature of the atmosphere that is causing the size changes, but instead it is the higher surface energy fluxes that arise from the increased air-sea temperature difference. Diagnostics show that fluxes of angular momentum from the environment are not responsible for the simulated TC size increases, even when the gradient in Earth

The primary objective is to continue to use innovative signal-processing methodologies to extract tropical cyclone (TC) structure information, including genesis likelihood from clouds clusters, intensity information, and wind field structure information from remote-sensing platforms in oceanic regions where in situ observations are sparse. This information is used to develop objective, accurate analyses of tropical cyclone wind structure and intensity.

The long-term goals of our research team are twofold: 1. To develop a suite of objective intensity estimation tools that are based on remote sensing data and multiparameter spatiotemporal analysis tools. 2. To understand the physical mechanisms giving rise to the observable signatures that are used for forecasting. Our principal objective is to develop an objective and automatic intensity estimator of Tropical Cyclones (TCs) based on satellite infrared (IR) imagery. The proposed methodology analyzes the TC s structure to estimate their intensity, which will be available every 30 minutes (or depending on image acquisition availability) for the Atlantic, Eastern North Pacific and Western North Pacific basins. We are investigating the underlying atmospheric dynamics by using mesoscale modeling and comparing the modeled storms to the measured signatures. The deviation-angle variance (DAV) technique was introduced in Pineros et al. (2008) as a procedure to objectively estimate the intensity of tropical cyclones. The level of axisymmetry of tropical cyclones is quantified by calcualting the gradient of the brightness temperature field in infrared images. The deviation-angle of these gradient vectors with respect to a radial line projected from a center indicates their level of alignment . Fig. 1a shows an example of this calculation for a single gradient vector in a brightness temperature field. In this case the center is located at the eye of the vortex. The calculation is done for every pixel within a chosen radius of the center point, and the variance of the distribution of angles quantifies the axisymmetry of the cyclone (Fig. 1b). The deviation-angle variance decreases as the majority of gradient vectors are pointing toward or away from the center., Prepared in collaboration with the Dept. of Atmospheric Sciences, Univ of Arizona, Tucson. The original document contains color images.

The long-term goal is to improve understanding of tropical cyclone genesis is through a research program that focuses on identifying the environmental and microphysical differences between developing and non-developing cloud clusters in the western North Pacific. The objective is to identify the environmental and microphysical differences between developing and non-developing cloud clusters in the western North Pacific. Specific investigations include: 1. detailed investigation of genesis using observations gathered during the TCS-08 field campaign. 2. detailed investigation of genesis using remote-sensed observations from platforms that are maintained on a more permanent basis including satellite-based infrared, visible, and microwave imagers and long-range lightning detectors. 3. utilizing model-based microphysical sensitivity studies to better understand the observed cloud microphysical differences between developing and non-developing cloud clusters. 4. generalized study that aims to build an ability to detect and classify developing and nondeveloping cloud clusters using remote-sensing platforms alone., The original document contains color images.

Our principal objective is to develop an objective and automatic intensity estimator of Tropical Cyclones (TCs) based on satellite infrared (IR) imagery. The proposed methodology analyzes the TC s structure to estimate their intensity, which will be available every 30 minutes (or depending on image acquisition availability) for the Atlantic, Eastern North Pacific and Western North Pacific basins. We are investigating the underlying atmospheric dynamics by using mesoscale modeling and comparing the modeled storms to the measured signatures.

The eastern North Pacific Ocean has the highest density of tropical cyclone genesis events of any tropical basin in the world, and many of these systems form near land before moving westward. However, despite the level of tropical cyclone activity in this basin, and the proximity of the main genesis region to land, tropical cyclone behavior in the eastern North Pacific has been relatively unexplored. When synoptic conditions are favorable, moisture from northward-moving tropical cyclones can be advected into northern Mexico and the southwestern United States, often leading to the development of summertime thunderstorms during the North American monsoon season. An interaction with a mid-latitude trough produces the most rainfall, and the spatial variability of precipitation is greatly affected by the complex topography of the region. Moisture can be advected from a tropical cyclone around the subtropical ridge in place for much of the eastern North Pacific hurricane season and contribute to precipitation. This ridge, when it extends westward over the Pacific Ocean, can also prevent tropical cyclone moisture from impacting the southwestern United States. Northward-moving tropical cyclones often enter an environment with decreasing sea surface temperatures, increasing vertical wind shear, and meridional air temperature and moisture gradients. These key ingredients for extratropical transition are generally present in the eastern North Pacific, but the subtropical ridge prevents many named systems from moving northward, and only 9% of eastern North Pacific tropical cyclones from 1970 to 2011 complete ET according to cyclone phase space. However, over half of the systems that do not complete ET dissipate as cold core cyclones, a structural change that has yet to be explored in other tropical basins. It is difficult to estimate tropical cyclone intensity in a vast ocean area with few direct measurements available. The deviation angle variance technique, an objective metho

To improve understanding of tropical cyclone genesis is through a research program that focuses on identifying the environmental and microphysical differences between developing and non-developing cloud clusters in the western North Pacific.

Our principal objective is to develop an objective and automatic intensity estimator of Tropical Cyclones (TCs) based on satellite infrared (IR) imagery. The proposed methodology analyzes the TC s structure to estimate their intensity, which will be available every 30 minutes (or depending on image acquisition availability) for the Atlantic, Eastern North Pacific and Western North Pacific basins. We are investigating the underlying atmospheric dynamics by using mesoscale modeling and comparing the modeled storms to the measured signatures.

Our overarching hypothesis is that there are significant microphysical differences between developing and non-developing cloud clusters. The objective is to identify the environmental and microphysical differences between developing and non-developing cloud clusters in the western North Pacific. Specific investigations include: (1) detailed investigation of genesis using observations gathered during the TCS-08 field campaign; (2) detailed investigation of genesis using remote-sensed observations from platforms that are maintained on a more permanent basis including satellite-based infrared, visible, and microwave imagers and long-range lightning detectors; (3) generalized study that aims to build an ability to detect and classify developing and non-developing cloud clusters using remote-sensing platforms alone., The original document contains color images.

In this project, we develop an objective and automatic intensity estimator of Tropical Cyclones (TCs) based on satellite infrared (IR) imagery. The proposed methodology analyzes the TC's shape or pattern to perform the intensity estimates, which will be available every 30 minutes (or depending on image acquisition availability) for the Atlantic, Eastern North Pacific and Western North Pacific basins. We are investigating the underlying atmospheric dynamics by using mesoscale modeling and comparing the modeled storms to the measured signatures.

To improve understanding of tropical cyclone genesis is through a research program that focuses on identifying the environmental and microphysical differences between developing and non-developing cloud clusters in the western North Pacific., The original document contains color images.

To improve understanding of tropical cyclone genesis through a research program combining high-resolution modeling and detailed observational studies to investigate detailed physical processes by which a tropical cyclone forms.

This document proposes an objective technique to estimate the intensity and predict the formation of tropical cyclones using infrared satellite imagery. As the tropical cyclone develops from an unstructured cloud cluster and intensifies the cloud structures become more axisymmetric around an identified reference point or center. This methodology processes the image gradient to measure the level of symmetry of cloud structures, which characterizes the degree of cloud organization of the tropical cyclone.The center of a cloud system is calculated by projecting and accumulating parallel lines to the gradient vectors. The point where the highest number of line intersections is located pinpoints a common point where the corresponding gradients are directed. This location is used as the center of the system. Next, a procedure that characterizes the departure of the weather system structure from axisymmetry is implemented. The deviation angle of each gradient vector relative to a radial line projected from the center is calculated. The variance of the set of deviation angles enclosed by a circular area around the center describes the axisymmetry of the system, and its behavior through time depicts its dynamics. Results are presented that show the time series of the deviation angle variances is well correlated with the National Hurricane Center best-track estimates.The formation of tropical cyclones is detected by extending the deviation-angle variance technique, it is calculated using every pixel in the scene as the center of the cloud system. Low angle variances indicate structures with high levels of axisimmetry, and these values are compared to a set of thresholds to determine whether a cloud structure can be considered as a vortex. The first detection in a sequence indicates a nascent storm. It was found that 86% of the tropical cyclones during 2004 and 2005 were detected 27 h on average before the National Hurricane Center classified them as tropical storms (33kt).Fin

To improve understanding of tropical cyclone genesis is through a research program that focuses on identifying the environmental and microphysical differences between developing and non-developing cloud clusters in the western North Pacific., The original document contains color images.

To improve understanding of tropical cyclone genesis through a research program combining high-resolution modeling and detailed observational studies to investigate detailed physical processes by which a tropical cyclone forms., Code 1 only. The original document contains color images.

To improve understanding of tropical cyclone genesis through a research program combining high-resolution modeling and detailed observational studies to investigate detailed physical processes by which a tropical cyclone forms., code 1 only.

Whether the tropical cyclone remnants will become a significant extratropical cyclone during the reintensification stage of extratropical transition is a complex problem because of the uncertainty in the tropical cyclone, the midlatitude circulation, the subtropical anticyclone, and the nonlinear interactions among these systems. In a previous study, the authors simulated the impact of the strength of the midlatitude circulation trough without changing its phasing with the tropical cyclone. In this study, the impact of phasing is simulated by fixing the initial position and amplitude of the midlatitude trough and varying the initial position of the tropical cyclone. The peak intensity of the extratropical cyclone following the extratropical transition is strongly dependent on the phasing, which leads to different degrees of interaction with the midlatitude baroclinic zone. Many aspects of the simulated circulation, temperature, and precipitation fields appear quite realistic for the reintensifying and dissipating cases. Threshold values of various parameters in quadrants near and far from the tropical cyclone are extracted that discriminate well between reintensifiers and dissipators. The selection and distribution of threshold parameters are consistent with the Petterssen type-B conceptual model for extratropical cyclone development. Thus, these simulations suggest that phasing between the tropical cyclone and the midlatitude trough is a critical factor in predicting the reintensification stage of extratropical transition.

To improve tropical cyclone structure and intensity prediction through a research program combining high-resolution modeling and detailed observational studies to investigate physical processes by which the structure and intensity of a tropical cyclone are modified. The objective is to investigate the physical processes that occur as a tropical cyclone interacts with the environment such that intensity and structure changes occur. Specific interactions being studied are with baroclinic environments in the midlatitudes during extratropical transition. During extratropical transition, radical changes to the storm structure occur as vertical wind shear and intruding cold, dry air from the midlatitudes erode the warm core. Re-intensification to a strong midlatitude system is possible. In cases in which forecast models poorly predicted the motion and re-intensification of the storm during these transitional periods, better understanding of these processes should improve motion and intensity forecasts., The original document contains color images.

The extratropical transition (ET) of tropical cyclones can sometimes result in rapid changes in the structure and intensity of the tropical cyclone. In particular, the second stage of ET can result in very different results from complete dissipation to rapid intensification into an intense midlatitude cyclone. Whether the tropical cyclone dissipates or reintensifies appears to be strongly dependent on the details of the midlatitude circulation. At the heart of the forecast problem is a lack of knowledge of the fundamental physical changes occurring during ET. Results are presented that show that the details of the midlatitude circulation are probably less important than the basic midlatitude structure for reintensification. Simulations presented here show that variations in the strength of the midlatitude upper-level trough have little impact on the subsequent reintensification of the tropical cyclone. Rather, it is more likely the energy of the background environmental state, and the phasing between the trough and TC that ultimately determine the intensity to which the cyclone can reintensify.

Recent observational and idealized modeling studies of tropical cyclones (TC) in environmental vertical wind shear have shown that the storms tend to have strong and persistent wave number one asymmetries, particularly in the rainfall and vertical velocity fields. The asymmetries in the tropical cyclone structure that develop under the influence of westerly wind shear have been shown to be significantly greater compared with those that develop under similar easterly shear strength. The intensity of the tropical cyclone is similarly impacted, with a TC in westerly shear being significantly weakened compared with a TC in easterly shear of the same magnitude. Tropical storm Chantal (2001) developed in strong and persistent westerly shear during the NASA CAMEX-4 field campaign in conjunction with the Hurricane Landfall (HL 2001) experiment. Whereas the storm struggled to develop throughout its lifetime, periods of strengthening and weakening can be directly related to the amount of vertical wind shear present in the environment. Using idealized model simulations that resemble the environment sampled by the NASA DC-8, ER-2 and NOAA P3 aircraft during Chantal’s struggle for survival, the relationships among the environmental vertical wind shear and the tropical cyclone wind and precipitation structure, and specifically the tropical cyclone intensity, will be examined.

To improve tropical cyclone track and intensity prediction through a research program combining high-resolution modeling and detailed observational studies to investigate physical processes by which the motion and structure of a tropical cyclone are modified.

The long-term goal is to improve tropical cyclone track and intensity prediction through a research program combining high resolution modeling and detailed observational studies to investigate physical processes by which the motion and structure of a tropical cyclone are modified. The objective is to investigate the physical processes that occur as a tropical cyclone interacts with the environment such that motion and structure changes occur. Specific interactions being studied are with baroclinic environments in the tropics and in the midlatitudes during extratropical transition, and with topography as a tropical storm makes landfall. As a storm makes landfall, significant asymmetries in the low-level wind structure are expected to develop with marked impact on precipitation and wind damage patterns. During extratropical transition, radical changes to the storm structure occur as the warm core is eroded by vertical wind shear and intruding cold, dry air from the midlatitudes. Reintensification to a strong midlatitude system is possible, and to further complicate matters, passage over islands with significant topographic features can occur during this transitioning process. In cases in which forecast models poorly predicted the motion and re-intensification of the storm during these transitional periods, better understanding of these processes should improve motion and intensity forecasts.

Long-term goals: To improve tropical cyclone track and intensity prediction through a research program combining high resolution modeling and detailed observational studies to investigate physical processes by which the motion and structure of a tropical cyclone are modified.

To improve tropical cyclone track and intensity prediction through a research program combining high resolution modeling and detailed observations to investigate physical processes by which the motion and structure of a tropical cyclone is modified.

To improve tropical cyclone track and intensity prediction through a research program combining high resolution modeling and detailed observations to investigate physical processes by which the motion and structure of a tropical cyclone is modified. The objective of this project is to investigate the physical processes that occur as a tropical cyclone interacts with the environment such that motion and structure changes occur. Specific interactions being studied are with mesoscale convective systems (MCS) that have been hypothesized to impact the development, motion, and structure of tropical cyclones, with baroclinic environments in the tropics and in the midlatitudes during extratropical transition, and with topography as a tropical storm makes landfall. As a storm makes landfall, significant asymmetries in the low-level wind structure are expected to develop with marked impact on precipitation and wind damage patterns. During extratropical transition, radical changes to the storm structure occur as the warm core is eroded by intruding cold, dry air from the midlatitudes. Re-intensification to a strong midlatitude system is possible, and to further complicate matters, passage over the Japan islands can occur during this transitioning period. In cases where forecast models did poorly in predicting the motion and re-intensification of the storm during these transitional periods, better understanding of these processes should improve motion and intensity forecasts., See also ADM002252.