Comprehensive Exam for MSU

Ageostrophic wind

Ageostrophic winds cross height lines and are the balance of PGF, Coriolis and friction. Friction acts to slow the winds and weakens the effect of the Coriolis force.

Know about and be able to explain the difference among projections, coordinates, datums, reference ellipsoids and geodesy. Be able to understand the importance of projections.

Geographic coordinate system is a reference system for locating spatial features on the earth's surface defined by latitude and longitude. These are spherical coordinates expressed in angles from the earth's center. Datum is a mathematical model of the Earth which serves as the reference or base calculating the geographic coordinates at a location. It includes the degree of offset from the center of the Earth with parameters of the ellipsoid, origin of the Earth's surface and the orientation. A projection converts geographic coordinates to projected coordinates. Reference ellipsoid model the geoid but may be distorted in areas. Geoid is the shape of the Earth. It is an irregular shape defined by its gravity fall.

What is georeferencing?

Georeferencing provides a relationship between images and objects on a coordinate system. Geometric transformations is the process of using a set of control points and transformation equations to register a raster image onto projected coordinates.

Geostrophic wind

Geostrophic wind is the balance of the PGF and the coriolis force. Supergeostrophic winds are found in the ridge and subgeostrophic are found in the trough. Geostrophic winds are parallel to height lines.

NWS text products (MOS)

Good for a non-active day. It uses a multiple linear regression model to determine the following: temperature, maximum and minimum temperature, PoP, thunderstorm probability, quantitive precipitation total, conditional probability of severe storms, conditional probability of freezing rain, conditional probability of snow, conditional precipitation type, ceiling height, visibility and obstruction of vision.

Understand and be able to apply the basic theory behind radar including Doppler radar and Dual-pol

Radar detects precipitation which depends on atmospheric conditions between the radar and the target, the tilt of the radar, precipitation characteristics, and radar characteristics. When our radar beam is sent out, we are getting the return beam that is collected and processed by the radar. This is called backscatter and is processed and indicated as "reflectivity." The reflectivity is determined by the size, shape, state and concentration of the particle. The equivalent reflectivity is the concentration and uniformally distributed small diameter water drops which could return the amount of power received. Doppler radar calculates the equivalent reflectivity, radial velocity and spectrum width. Dual-pol allows forecasters to get detail in the radial and traverse directions.

SPC products

Severe Thunderstorm Watches, Tornado Watches, Particularly Dangerous Situation (PDS) Watches, Public Severe Weather Outlooks (PWO), and Mesoscale Discussions (MD)

Know about geodatabases and the other types of databases. Know what relationship cardinality is.

Geodatabases use points, polygons, and polylines to represent vector-based spatial features. In ArcGIS, there are the following geodatabases: personal, file and enterprise. The enterprise is the largest. There are different types of databases including a simple list, index list like a phone book, flat file like Excel, and relational database like MS Access. The relational database is a collection of tables that are connected by keys with cardinality of one-to-one, one-to-many, many-to-one and many-to-many.

Lightning: Formation, Climatology, Safety

The process of lightning formation is as follows: 1 a stepped leader moves quickly down to earth, 2 the leader ionizes the air and produces a conductive path, 3 a very bright powerful return stroke transfers charge, 4 produces a shockwave known as thunder, 5 with a new step leader "dart leader" that prepares channel for another return stroke. Florida has the most lightning across CONUS. Southeastern South America including Brazil/Argentina and central Africa have a lot of lightning. When thunderstorms nearby, avoid open fields, trees and water.

Adiabatic processes

Adiabatic processes include the dry adiabatic lapse rate (DALR), the saturated adiabatic lapse rate (SALR), and the superadiabatic lapse rate. Adiabatic means there is no exchange of heat with the environment.

Different precipitation types

Precipitation types include rain, snow, sleet (partially melted snowflakes that refreeze before hitting the ground) and freezing rain (rain that freezes upon contact with the ground).

Heat

A form of motion that is translational, vibrational or rotational.

Basic terminology (precision, accuracy, sample, population)

Precision is how close the data are to each other. Accuracy is how close data is to the correct answer. Sample is a small subset of the population. Population includes all possible outcomes.

Upper air charts (all significant levels) /Surface charts

200 millibars, 250 millibars and 300 millibars are generally the critical level for the jet stream. 200 is the summer. 300 is the winter. 250 is transitional seasons like fall/spring. 500 millibars is the level of non-divergence for looking for vorticity. 700 millibars give the flow of the air mass thunderstorm and helps to determine the vertical velocities. 850 millibars is for thermal/moisture advection.

Know how visible, IR and water vapor images are captured and the difference between them

A bright cloud on VIS is usually very thick. On IR, this means the cloud is colder and higher up. Upper-level clouds will appear stretched and fibrous. Height is best to ID on IR and texture on VIS. VIS shows outer space as black. Thin cirrus clouds will appear bright white. Most water is dark but the sun glint can make it appear brighter. On IR, space will be white. The coldest temperature will be the brightest. On WV, space is white. The higher the clouds, the cooler the clouds. Low clouds are not visible on WV because the temperature is so close to the ground.

Derechos: Types, Climatology, Formation

A derecho is a wind event resulting from a family of downbursts clusters It is indicated on radar by a bow echo measuring from 20-200 km and lasting for many hours. It can be either serial or progressive. Serial is consisting of a line of small bow echoes or HP supercells. Tornadoes or more likely with this type. Progressive is when the entire line is forming a bow. Derechos must have significant WAA and weak boundary parallel to the upper air level flow. Derechos are much of an eastern weather event with 1 derecho every 4 years for the most part with 1 derecho every 2 years, 1 derecho every year and 4 derechos every 3 years as you go further south (OK/AK/MO border).

Be able to define heating, cooling and growing degree days, ethnometeorology, probability of precipitation, phenology, thermoregulation, amplification or attenuation of risk, PETS Act, human-animal bond.

A heating degree day are a measure of how cold the temperature was on a given day or during a period of days. The cooling degree days are a measure of how hot the temperature was on a given day or during a period of days. Growing degree days are used to estimate the growth and development of plants and insects during the growing season. Ethnometeorology are the practices of different cultures and farmers on how to predict the weather. It is a scientific trend in studying the ethnie specificity of traditional ideas of different peoples of the world linked with the weather, in the context of modern ideas of natural science. The probability of precipitation is a combination of a chance the rain would occur and the amount of area it will cover. Phenology is the timing of seasonal activities/life events. It is the study of cyclic and seasonal natural phenomena, especially in relation to climate and plant and animal life. Thermoregulation is a process that allows your body to maintain its core internal temperature. Amplificatio/attenuation of risk are different social interactions and societal functions that impact the perception of risk. The PETS Act requires that emergency plans address sheltering of pets and animals, working animals, ensuring responder safety at a disaster scene, people responsible for pets. The human-animal bond answers: why do people not evacuate pets? Outside dogs, cats without carriers, don't expect to be gone long.

What is a model? What are some model applications? Know the elements of models and the various types of models that can be built.

A model helps to process, display and integrate different data. This can be a data management tool. Models can be vector based or raster. Model can be descriptive, perspective (offers a prediction), deterministic, stochastic (considers randomness so likely a probability or statistical model), dynamic (shows changes in spatial data over time), static (shows the state at a given time), deductive (based on a series of scientific theories) and inductive (derived from data). There are binary models (use zero for things that don't meet criteria and 1 for things that do), index models (calculates the index value of each unit area and produces a ranked map based on the index values), regression models (relates dependent variables to a number of independent variables) and processing models (integrates existing knowledge about the environmental process in the real world to a set of relationships using equations for quantifying the process).

Squall Lines and Bow Echoes: Key features, Development, Severity

A squall line are multicell storms that form in a linear pattern and associated with a pattern. They are usually ahead of a cold front. Line Echo Wave Patterns (LEWPs) are key features and indicate uneven surface flow and severe threat. A bow echo is a bow shaped system of convective cells about 20 to 120 km long and usually produces large areas of damaging winds. During the early and mature stage, you are likely to see localized hail, downbursts and small tornadoes. During its mature stage, you are likely to see enhanced system-scale winds that are associated with the rear-inflow jet.

Equilibrium

A state in which system's properties remain unchanged—when all the components are equal and not changing much. We generally assume equilibrium to make it easier. Mechanical equilibrium is when the system doesn't undergo accelerations, so the velocity stays the same. Material equilibrium is when there is no net transfer of matter. (You can exchange but the net is 0.) Thermal equilibrium is no net transfer of energy. Thermodynamic equilibrium is when what's inside and outside doesn't change.

Types of systems and states

A system is any chunk of matter that we are dealing with. There are different types like open, which allows matter to enter and exit a system like a glass of water with no lid, but a closed system cannot change matter with outside like a balloon. An isolated system is always a closed system. It cannot exchange matter or energy with the surrounding like a thermostat. The state of the system is defined by the position and momentum of every piece of matter in it.

Be able to describe documented and possible animal responses to climate change.

Animals might shift timing of life cycle events, shift range/change density in range, change morphology (of body or egg), or go extinct. Animals may also migrate at different times; some might die out if it's too hot/cold. Extinction is usually caused by loss of habitat or could be because of nonnative plants. Ex: warming in ocean is leading to less krill, which is domino effect and less birds and less seals.

Be able to define the following key terms from the Research Methods class and provide examples (applied, basic, theory, hypothesis, parsimony, inductive and deductive approaches)

Applied research involves development of an application, quantification or prediction of atmospheric phenomena like a case study. Basic is focused on the advancement of knowledge then solving a problem. An example would be medicine, education, psychology and technology. Theory helps understand the "why." An example theoretical research question is: how do tornadoes form? Hypothesis is an educated guess. Parsimony principle states that theories should be as simple as possible. Example: you make a simple conclusion based on a lot of evidence. Deductive is based on prior knowledge and inductive is based on fact.

Tropical cyclone structure Structure of the core and outer regions Eye and eyewall processes Eyewall replacement cycle Rainbands (types and distribution)

As the radius increases, the modified Rankin vortex decreases, the absolute angular momentum increases, inertial period increases, and Rossby radius of deformation. The core of the TC includes rainbands, convective ring, moat, eyewall and eye. Wind structure within the core is: radius of max winds generally in the eyewall, sharp increase in speed near the radius of maximum winds, winds decrease aloft, max winds tilt outward with height, max winds found in the right-front quadrant of the cyclone, and strongest horizontal temperature gradient are near the radius of max winds. Inner region has small Rossby radius of deformation and outer region has large Rossby radius of deformation. Subsidence is common in the outer region in areas of weak upward motion. The conceptual model of forming the eye is: 1 the air spirals inward toward the center due to conservation of angular momentum, 2 at some distance near the center of the TC, the dissipation of angular momentum can no longer keep up with the horizontal advection, 3 the horizontal convergence of angular momentum leads to an increase winds above the value that the pressure gradient can support, 4 convergence will lead to upward motion, which results in convection in the eyewall, 5 upward motion in the eyewall results in outflow aloft and high perturbation pressure over the center of the storm, 6 the upper-level pressure perturbation and the low level divergence results in compensation subsidence. Outer convective rings form and causes inner ring to dissipate because of 1 subsidence from outer ring suppresses convection and 2 the outer ring takes away the inner ring of inflow. Tends to occur in intense storms. Types of rainbands include moving spiral bands (rotate with circulation), convective rings (enclose the cyclone), and principal spiral bands (non-moving that wrap into TC) .

What are the Boolean operators and in which situation would you use each?

Attribute data queries can be done with Boolean operators including and, or, not and "and or." And is looking for the intersection, but or is looking for what can meet the criteria.

Know the ways distances are calculated and used in GIS

Calculating distance is dependent on the geometry type of the features as well as other factors such as coordinate system. However, there are three basic rules, described in detail below, that determine how distance is calculated. 1. The distance between two points is the straight line connecting the points. 2. Distance from a point to a line is either the perpendicular or the closest vertex. 3. Distance between polylines is determined by segment vertices.

Cloud and precipitation patterns Vertical temperature and motion profiles Cloud types and distribution Diurnal cloud cycles

Clouds and precip are very correlated over the tropics. The tropopause is higher in the tropics due to hypsometric equation. Mean vertical motion at 500 mb is well correlated with mean precipitation minus evaporation. Cumuliform clouds are dominate either doldrum cumulus or trade-wind cumulus are available at all levels. Cumulonimbus, stratus and stratocumulus clouds are also common. Altocumulus or altostratus are also associated with disturbances. Cirroform clouds are at much higher heights in the tropics. For coastal/island regions, land/sea breezes are the primary factor in cloudiness and rainfall variations. Large islands have an afternoon maximum due to daytime heating, land/sea breezes and mountain/valley breezes.

Cluster analysis Hierarchical techniques Random center techniques (k-means)

Cluster analysis is the statistical technique of grouping data that has similar characteristics. Two primary types include hierarchical clustering or non-hierarchal clustering. Most common way is based on distance using the Euclidean distance. The dendrogram is a visualization of the hierarchical clustering. Ward's method is another technique that minimizes the sum of the variance for the data within each cluster. K-means is the non-hierarchical clustering method. This a method of choosing your own center and number of clusters before starting. Then calculate the distance from these centers and your data points, grouping the data closest to its center and average the data points in each group. This is the new center.

Probability theory overview

Compliment of an event is the probability of the event minus 1. Union is joining two events in a single layer. Intersection finds common subevents between larger events. Conditional probability is probability of one event given another. Independent if one event does not effect the other. Baye's theorem is a way to calculate the conditional probability by a simple equation.

Coriolis

Coriolis effect is the apparent deflection of wind due to the rotation of the Earth. It is to the right in the northern hemisphere and to the left in the southern hemisphere. It is maximum at the poles and minimum at the equator. It is proportional to the wind speed.

Measures of association (correlation, covariance)

Covariance is how one dataset varies as compared to another. Correlation is the covariance that is normalized by dividing the product of the two samples. This number ranges from -1 to 1.

Be able to compare/contrast different research methods

Different research methods include secondary data analysis, content analysis, survey, focus groups, interview (structured or unstructured), observations and experiments. These are in order from least human interaction to most. In behavioral observations, you can't record everything, and your presence can alter the behavior of what you are observing, but it is qualitative and rich in data. In an experimental method, you can isolate the effects of a certain variable but difficult to create experimental conditions. Focus groups can allow for good exploring of a topic and opinions but some may be dominate in a group. Interviews can lead to rich data, but can take more time to analyze. Surveys can provide quantitative data on large groups but can be expensive, time consuming and receive low response rate.

Know about digital elevation models (DEM).

Digital elevation model are really useful to model elevation/topography. They are rasters of elevation. The USGS one has a 30 m horizontal resolution and 15 m vertical resolution.

Local and diurnal circulations Sea/land breeze Mountain/valley breeze Stress induced convergence boundary

Diurnal variations of both solar radiation and temperature are larger than annual variations. So, mesoscale atmospheric processes dominate the tropical circulation. Land and sea breezes are caused by the differential heating across the land and water. Sea breeze occurs during the day and the land breeze occurs at night. Valley breezes occur in the afternoon as convective uplift causes convergence at higher elevations which leads to cloudiness over mountains clear skies in the valley. Mountain breezes occur at night due to subsidence that leads to convergence over valleys (clouds over valleys). For the stress induced convergence, if there is a high offshore, there will be divergence and drier conditions along the coast. If high pressure is inland, there will be convergence and more moist conditions over the coast.

Know about error and the different types of errors.

Errors in DEMs are usually classified as either sinks or peaks. A sink is an area surrounded by higher elevation values and is also referred to as a depression or pit. This is an area of internal drainage. Some of these may be natural, particularly in glacial or karst areas (Mark 1988), although many sinks are imperfections in the DEM. Likewise, a spike, or peak, is an area surrounded by cells of lower value. These are more commonly natural features and are less detrimental to the calculation of flow direction.

Be able to describe each step of the emergency planning process (mitigation, preparedness, response and recovery) and give or recognize examples of each.

FEMA coordinates the federal government's role following a disaster. The first step is mitigation which are activities done to prevent or reduce the future impact of a hazard. This is undertaken before the event is imminent or after the event occurs (to plan for the future). This is a long-term initiative. Examples include buying insurance against a particular hazard, drinking extra water on a hot, dry day, flood control projects, levees, sea walls or dunes. The second step is preparedness which is the planning made prior to an expected event. This puts you in a state of readiness to respond. This is a short-term initiative including evacuation plans, stocking up on food or water, developing emergency response organizations or taking an umbrella when you expect rain. The next step is response which is the implementation of an emergency plan. This includes taking shelter, evacuating, staying off roads during icy conditions, and deploying emergency services or first responders. The last step is recovery wherein you are returning to pre-event conditions including reconstruction, fixing any damage to your home, and repaving washed out roads. This is after basic needs are met.

Data distributions (discrete and continuous)

For a discrete distribution, the expected central value is based of the distribution is defined by a summation, but a continuous distribution we use an integral instead of a discrete sum. Discrete have a finite number of possible data points. (Example: binomial distribution, Poisson distribution) . Continuous have an infinite number of possibilities. (Example: normal distribution, probability density function, cumulative density function, Data distributions are hypothetical "molds" of data that we use to help us understand the characteristics of the data. Parameters of data distributions are described by Greek letters.

Know about GPS and its uses.

GPS is a device for telling us where we on surface. It's a similar concept to the dead reckoning wherein you know the time, direction and speed then you can determine your location. This is substituting time for distance. This can be done very similarly in radio navigation and celestial with stars. A GPS consists of a satellite, receiver, and a monitoring station. The signal is emitted and picked by the receiver. We know the time and rate so we can determine the distance.

Be able to explain the advantages of using a GIS over using another type of program like Google Earth. Meaning, what can you do in GIS that you cannot do in Google Earth?

Generically speaking, google earth is more user friendly for the average joe. It's free and straightforward. GIS is not free and more complex, so it's more for a working professional. On GIS systems, you can do great analysis and figure out relationships between different features. Unlike Google Earth which is just looking at point a and point b, so there is no analysis and spatial relationship diagnosis.

What is geocoding? What do you need to be able to perform a geocoding operation?

Geocoding is using tabular data and converting it to x, y table. Address geocoding is specifically looking at addresses. Each segment of an address has important spatial information including house number, street name, city, state and zip code. In order to geocode with addresses, you must have a table of addresses and a geocoding reference database that includes the topology with to and from nodes where things are. Address geocoding doesn't find an actual address but a spot on a street.

What heuristics and biases influence people's risk perception? Be able to identify or give examples.

Heuristics : Judgement made on the fly using little information. Straight forward rule of thumb made off past experience. Cognitive tools that help us make decisions. Availability Bias: A mental shortcut that relies on immediate examples that come to a given person's mind when evaluating a specific topic, concept method or decision. Optimistic Bias: The belief that an individual is less likely to experience a negative event. (that would never happen to me). Representativeness: Simple described as assessing similarity of objects and organizing them based around the category prototype. Affect: A mental shortcut that allows people to make decisions and solve problems quickly and efficiently, in which current fear, pleasure, surprise etc. influence decisions. Smith and Petley created a process people go through when determining risk: first it's risk identification, then risk estimation, then risk evaluation. Some of the factors considered are statistical inference, personal awareness, magnitude/frequency, economic costs, personal experience, cost/benefit analysis, community policy, individual action. In the public, there are some characteristics that are judged more tolerable than others. Related to weather: some types of weather have different risk values, so a tornado is an immediate impact that you need to act and respond on quickly, heat and cold is something you have to consider but not immediately, and climate change doesn't directly impact you on a daily basis so the risk is much lower.

Trends: Radar Signatures and what they indicate. Hook Echo, Kidney Bean, Three-Body Scatter Spikes, MARC, Rotating Comma Head Forecasting and Analysis

Hook Echo indicates a strong supercell. The kidney bean shape is for an HP supercell. The TBSS is a hail indication on the radar. Mid-altitude radial convergence (MARC) signature is an area of locally enhanced convergence found embedded within a region of convergence. It is usually about 60 to 120 km in length and 2 to 6 km in width. Northern end of bowing line of storms has a more enhanced cyclonic flow because of the coriolis force acting to rotate it.

Be able to describe the various categories of statistical tests and provide examples of when you would use them.

Hypothesis testing: you have a null hypothesis which is the opposite of what you desire the outcome to be. If it falls outside of the probable region, you can reject the null. T-test is a test on means. F-test is a test on variances, and chi squared is a test on distribution shapes.

Atmospheric stability

If a parcel is warmer than its environment it will continue to rise. This is considered an unstable environment. If a parcel is colder than its environment it will sink or not rise. On a sounding, the area above the LFC where the parcel is warmer than the environment is known as the convective available potential energy (CAPE). The convective inhibition (CIN) is the area the parcel has to overcome. This is where a parcel is colder than its environment. This can be degraded by daytime heating and/or an increase in moisture. Severe weather nerds like CIN in the morning because the buildup of CAPE throughout the day will lead to good severe weather by the end of the day.

Tropical cyclone thermodynamics Conservation of energy Carnot cycle

If a parcel moves, the surrounding pressure will act on a parcel. So, the environment is doing work on the parcel. According to the first law of thermodynamics, energy cannot be created or destroyed. According to the second law, in an isolated system, entropy never decreases and it is the change in heat relative to the temperature during a reversible process. The Carnot cycle is a cyclic thermodynamic engine that converts heat from some source into work through 4 steps: reversible isothermal expansion, reversible adiabatic expansion, reversible isothermal compression and reversible adiabatic compression.

Enhanced Fujita Scale

In 1971, Ted Fujita created the Fujita scale that was based on the maximum wind speed inside the funnel. The main challenge was that it was consistent. The Wind Science and Engineering Center of Texas Tech created the Enhanced Fujita which was operational on February 1, 2007. Wind estimates are based on damage seen and includes 28 damage indicators with degrees of damage and 3-second wind gust estimated at the point of damage are all considered.

State variables

In a 3D system with T point masses, there must be 6T variables known at a given time. To make it feasible, we take the average within the system. This is known as the thermodynamic approach. This is described by internal energy (U), volume (V), and the # of moles (n). If not in thermodynamic equilibrium, we need more variables. State variables that can replace U,V, n include density (p), enthalpy (H), entropy (S), mass (m), pressure (p), and temperature (T). The number of state variables is 2 + the number of components. Meteorology usually uses entropy, pressure and temperature.

Satellite imagery (visible, IR, water vapor) and feature ID

In satellite imagery, visible can show texture and is indicated by brightness. The texture is visible because the higher clouds will cast a shadow beneath. It is only available when the sun is up. IR measures thermal radiation and is showing the temperatures of the returns. It is available 24/7. Colder temperatures indicate taller features. Water vapor is showing the moisture content in the mid to upper levels. Higher concentrations appear more "white." Meteorologists generally use satellite imagery to ID cloud streets, sea breeze fronts, thunderstorm outflow boundaries, etc. Satellite enhancements allow you to change the color of the cloud. The MB curve is the mid-latitude t-storm curve to show contrasts in the tops of t-storms. They can ID a MCC.

Internal energy

Internal energy is the sum of the internal kinetic energy and the internal potential energy. If the internal energy does not change with time, it is conserved.

Kinetic Theory of Ideal Gases

It helps understand momentum. Before impact, p=mV. After impact, the molecules move in the opposite direction, so "p=-mv." The total change is 2mpV so the dP=2mVdN. This is assuming the molecules have the same speed and temperature. The total change in momentum is dP=2mV^2(N/6V)sdt.

Models of Tornadogenesis: Lemon-Doswell, Klemp Tornado Lifecycle Tornado Climatology, Seasonality

Lemon-Doswell method starts with surface inflow moving into the storm with 4 km flow away from the storm and 9 km flow aloft and the forward flank downdraft pushing aloft. In step 2, the rear flank downdraft is now stronger and the occluded front starts to form and cold cut pool ahead of FFD. In step 3, we see the tornado drop. The RFD is getting larger and 4 km flow is impended. Step 4, the updraft is beginning to collapse with a new updraft forming possibly. This method helps to determine the likelihood of a tornadic supercell. The Klemp model is similar to Lemon & Doswell but the pattern evolution is different. Klemp believes the tornado phase begins after the low level rotation intensifies first. Tornadoes form at stage C of the Lemon and Doswell model when the BWER collapses and the storm top lowers. Step 1 is the dust whirl stage which looks like a dust devil and the vortex is invisible because pressure isn't low enough to see the cloud. Step 2 is the organization stage where you see the funnel cloud. Step 3 is the mature stage where the vortex is at its greatest intensity. The wall cloud is well organized and rotation is visible. Stage 4 is the shrinking stage and Stage 5 is decay. Most tornado watches are in the deep south but more are in Texas, (Tornado Alley). There is warm moist air from the south and cold Canadian air from the north and off the Rockies. A lot in Florida associated with hurricanes but are generally weak. Washington, AL has the most tornado watches.

Regression Multivariate linear regression (including stepwise)

Linear regression involves using a predictor and a predictand and fitting a linear function to the x-y relationship. By reducing the model size down to the most significant predictor and producing the same results is the basis of stepwise regression. The stepwise will add in one variable at a time starting with the most significant predictor. You can use the model to predict data.

Know map algebra, neighborhood, local, and zonal operations? How and when would these tools be used? What results would be given from these operations?

Map algebra is basically doing math with maps, but with only raster data. Map algebra uses math like operations like addition and multiplication. Local operations are the simplest approach to map algebra where you have the cell-by-cell stacked and you have 2 rasters stacked on top of each other. Global operations is a bulk operation like if you want to add 1 to every grid cells. Neighborhood operations are spatial functions that compute an output value using neighborhood values. Zonal operations apply a math function to a group of cells within a specified zone. For example, a zone could be a vector and raster format.

Measures of central tendency (mean, median, mode)

Mean is the average. The median is the middle number. The mode is the number repeated most often.

Moisture and saturation

Mixing ratio tells us how much water vapor is in the air. It is ratio between mass of water vapor to mass of dry air. Saturation mixing ratio is the mixing ratio if the air is saturated and its temperature dependent. If the air is saturated and it is temperature dependent. Higher temperatures have higher mixing ratios. As we move up in the atmosphere, the air cools and we reach condensation and the moisture is no longer a factor. There is less water vapor present as we move up in the atmosphere. Vapor pressure is the pressure exerted by water vapor. Water vapor makes up 0-4% of the air. There is a greater percentage in warmer climates. Vapor pressure then ranges from 0 to 40 millibars. Saturation vapor pressure is the maximum amount of vapor pressure at a given temperature. Saturation has been reached if vapor pressure and saturation vapor pressure are the same.

Non-parametric methods (bootstrapping and permutation tests)

Non parametric methods are for data that is not normally distributed including the Mann-Whitney U test, Mann-Whitney-Wilcoxon test and the Wilcoxon rank sum test. It is done based on rankings of each sample. Bootstrapping is a method of resampling that samples with a replacement a user-defined number of times to produce a normally distributed dataset. A permutation test doesn't require normality but can compare means. The test resamples datasets in one giant pool and compares differences from within the pool to differences within the dataset. The differences will be similar if they have similar means.

NWP Models

Numerical weather prediction is predicting the future state of the atmosphere using physical equations. The models can be "mesoscale," "regional" or "global."

Geopotential Heights and significance of thickness of layers of the atmosphere

On pressure maps, you are seeing height lines. Height lines are higher when temperatures are warmer. The thickness of the layer is dependent on the hypsometric equation.

Know both POES and GOES platforms and the difference between them

POES are polar orbiting environmental satellites. They are called polar orbiters because they are close pole to pole. They are also sun-synchronous and follow the orbit of the sun. They happen at the same time everyday. It does about 14 orbits in a day. The POES collect data on ascending and descending branches. The ascending is during the day and descending is at night. AVRR is an example. GEOS is the geostationary operational environmental satellites. This is different from POES because it is stationary overhead. It is geosynchronous because it remains at a height of 22,400 feet above the earth's surface. The polar regions are not captured as well.

How is weather and health related? What are some conditions that are influenced by weather?

People consider health when deciding how to react to weather, so if their health is at risk they might take it more seriously. Weather can impact health on an individual scale in regards to Vitamin D levels and also causing people to be sad if they don't have serotonin and happy drugs from sunshine. Happiness is influenced by weather. When people are exposed to more sunlight, they are happier.

Percentile statistics (quartiles, IQR, five number summary)

Percent quartiles includes 25%.50%, 75% and 100%. It breaks the dataset into 4 parts. The IQR is the difference in the two quartiles (25% and 75%) to give a measure of spread about the center. The five number summary includes the mean, first quartile, third quartile, minimum value and maximum value.

Know the various methods of vector analysis including overlays, buffers, queries, and geoprocessing.

Query is a tool to inquire about the data. Map overlays is stacking the layers like pancakes with point in polygon, line in polygon or polygon in polygon. The formula for doing an overlay is input feature + overlay feature (must be polygon) = output feature (same type as input). Buffers divide the map into two areas one with items that meet the criteria and one that doesn't. Geoprocessing includes the dissolve, clip, append, select, erase, union, update and split tools.

Tropical cyclone dynamics Rankine vortices Distribution of angular momentum Vortex stability Rossby radius of deformation

Rankine vortices are a 2-D circular flow model defined by a rotating inner region that is undergoing solid (V/r=constant) and an outer region with zero vorticity(V*r=constant). The distribution of angular momentum usually has a peak towards in the core and gradually decreases in speed as the radius increases. Inertial stability of a vortex is based on the frequency. If the frequency is positive, it is inertially stable. If the frequency is zero, it is inertially neutral. If the frequency is less than zero, it is inertially unstable. The more inertially stable a vortex is, the less it will interact horizontally with its environment. Rossby radius of deformation is a fundamental horizontal length scale for a disturbance in a rotating fluid. This is the length scale at which rotational effects become as important as buoyancy or gravity wave effects in the evolution of the flow about some disturbance. If the size of the disturbance is comparable or larger than the Rossby radius of deformation, then the wind will adjust to the mass field. If smaller, the disturbance will die quickly.

Vorticity - Absolute, Relative (shear and curvature), Planetary

Relative vorticity is based on wind flow and wind speed it is the total of curvature and shear. Planetary vorticity is due to Earth's rotation. This is included by the Coriolis parameter. Absolute vorticity is the total of relative vorticity and planetary vorticity. Positive relative vorticity spins CCW and cyclonically with faster winds to the south. Negative relative vorticity spins CW and anticyclonic with faster winds to the north.

Understand and be able to apply the basic theory behind remote sensing

Remote sensing is measuring something without the system being in contact with the thing being measured. This is helpful for gathering data were in-situ is not as readily available like in the middle of the ocean. It must be processed but a lot easier to manipulate data on the computer. EM radiation is the basis of all remote sensing on earth. Everything with a temperature above absolute zero emits radiation that be measured. So, we get that data and interpret it.

What factors influence response to hazards (e.g. hurricane evacuation, tornado sheltering, driving through flood)

Response varies from hazard to hazard. For hurricanes, previous experiences often drive evacuation plans, as well as status of insurance on belongings. Demographic information also dictates response (poor, black, etc. less likely to evacuate.) Reasons given for staying often include feeling of safety, desire to protect property from storm or looters, work obligations and inconvenience of leaving. Driving through floods is usually as a result of a misjudgment of depth. Tornado sheltering a matter of time and education (knowing the risks). People need to not only know what the hazard is, but how it will affect. them. Risk perception can motivate or reduce action. People do not like to leave at night. Most go to friends/family, less than 15% go to public shelter, rest go to hotels, work, church. Variables that determine evacuation: vulnerability of the location, action taken by public authorities, storm specific threat factors. People do not leave because they felt safe, protect property, work obligations, and inconvenience of leaving.

What is cultural theory of risk perception? How do the worldviews relate to climate change research?

Risk is embedded in culture, Social organizations emphasize those risks that reinforce the order that holds the group together. Examples of cultural role: dependent on government or belief that events are acts of God. Local culture could include beliefs such as tornado can't hit a city or the hills will protect us. There are four rationalities in culture: the fatalist: it doesn't matter who you vote for, the hierarchist: a place for everything, the individualist: the bottom line and the egalitarian: tread lightly on earth, Personal culture impacts views on environment: Personality (do you take risks? Do you like nature?), Experience (how often are you exposed to hazards?) and Demographics (education, income, gender, race).

Indices (Lifted Index, CAPE, SWEAT, EHI etc.)

SBCAPE is the amount of potential energy available for a parcel originating at the surface and then lifted to the LFC.CIN is the amount of energy the parcel will need to overcome before development can begin. The MLCAPE is the mean potential energy that is available to a parcel of air that is lower than 100 millibars when lifted to the LFC. The most unstable CAPE is the total amount of energy that is available to the most unstable air that is located within the lowest 300 millibars of the atmosphere while being lifted to the LFC. The lifted parcel level is where the largest CAPE is elevated. Normalized CAPE is the CAPE divided by the depth of the buoyancy layer. The downdraft CAPE is the estimated potential strength of the rain-cooled downdraft from thunderstorm convection. SRH measures potential for cyclonic updraft rotation in right-moving supercells. The EHI is the storm rotation likelihood based on the combination of CAPE and SRH. SWEAT (Severe Weather Threat Index) is an index for severe weather potential. Lifted Index is the temperature between the environment and an air parcel lifted adiabatically. The more negative the more severe weather is likely.

What is a spatial query?

Spatial data query helps to retrieve information from a map. There are multiple types of spatial arrangements including containment, intersect, proximity and adjacency.

Know about spatial interpolation, pattern analysis, and surface analysis processes in detail.

Spatial interpolation is the process of using points with known values to estimate values at other points. It's usually applied to raster with estimates for all cells. Spatial interpolation is therefore a means of creating data from sample points. Spatial pattern analysis provide insights about where things occur, their distribution or the arrangement of data aligns with other features. Surface analysis will show surface conditions plotted from reported data or generated by computer models. Surface analyst in GIS will show contour, slope, aspect and hill shade maps.

Be able to identify cloud types and cloud features given a satellite image

Stratiform clouds look smooth with a flat op. Fog is a stratiform cloud. Cumuliform clouds appear lumpy on VIS and dark/medium grey on IR. Towering cumulus and cumulonimbus appear bright on IR/VIS. Mid-level/alto clouds can look like cumulus or super flat like stratus. Upper-level clouds look wispy. Cloud street is a narrow cloud band with individual cloud cells not connected. Cloud line is a narrow cloud band with cloud cells joined together. Cloud fingers are extensions that extend south of a frontal boundary.

Tropical cyclogenesis Synoptic-scale influences Diurnal influences Factors associated with intensity fluctuations Intensification mechanisms

TCs are generated based on the intensity of feedback mechanisms like latent heat release, higher wind speeds, convective motion and frictional dissipation. Any enhancement of vorticity is favorable for TC formation. Existing storms can influence: if the storm has yet to recurve, the path ahead is unfavorable for formation but behind it is. Outflow from an existing storm can provide too much shear and suppress formation. NE quadrant outflow jet is enhanced by the subtropical jet, a tropical upper tropospheric trough (TUTT), a deep mid-latitude trough and an upper level cold low. Convection is enhanced during early morning hours. Factors that can influence the intensity of the TC include the SST variations, land interactions, enhanced/suppressed outflow, and increased vertical shear.

What is an analysis mask and what is its function? When would you use one?

The analysis mask limits analysis to cells that do not carry the cell value of 'no data.' It divides the grid into two parts: what you want to work with and what you don't. What you don't want to work with will be labeled as NoData in the output. In the example illustration, we have an input of the global map, the mask is a weird blob shape and then when you apply the tool, you get an output of the global map only within that weird blob shape with the rest as blank.

Teleconnections

Teleconnections are circulation patterns that occur in separated regions of the globe that can affect what weather is experienced in other parts. This includes the El Nino Southern Oscillation, Madden Julian Oscillation, North Atlantic Oscillation, Arctic Oscillation, Pacific North American pattern and the Pacific Decadal Oscillation. ENSO occurs because of the change in pressure between Darwin Australia and Tahiti, which is supposed to be a high over Tahiti and low over Darwin. Higher than normal pressure at Darwin and lower than normal pressure over Darwin which leads to weaker PGF and weaker trade winds. This is a warm phase because upwelling isn't occurring. This is known as El Nino. The opposite results in La Nina. La Nina leads to upwelling on the coast of South America around Ecuador and Peru which means better fishing industry because the tiny baby fish are being brought to the surface. Walker Circulation is when there is a high off the west coast and a low off of the east coast of Asia that shifts. During La Nina, the neutral circulation strengthens. In El Nino, the low shifts eastward off the west coast of CONUS. During El Nino, wet and cool across southern US and the subtropical jet is amplified. La Nina leads to amplified jet across the US and colder and increased storms across northern US and warm/dry across south. La Nina leads to increased tropical activity because of weaker westerlies. Madden Julian Oscillation is an eastward propagating disturbance that has 8 phases. It has a convective rising phase and a suppressed sinking phase. NAO is the difference in surface pressures between the Azores high and the Icelandic polar low. In the positive phase, there is stronger than normal Azores High and Icelandic low. This leads to increase in frequency and intensity of storms crossing the Atlantic Ocean and milder/wetter across eastern US. Negative phase leads to decreased PGF and arctic outbreaks. AO similar to NAO.PNA has a trough ridge trough pattern around the globe. Positive is more amplified. PDO is like ENSO but based on SST. Positive phase leads to cooler SSTs in the central North Pacific and warm SSTs along the west coast of North America. This is similar to El Nino.

Mesoscale Convective Complexes: Characteristics and Severity, Climatology Mesoscale Convective Systems, Types and sub-types, Development of the cold pool

The Coriolis force can change the structure of a large MCS and as time progresses, the horizontal vorticity along the cold pool is tilted on each end called line-end vortices. Linear MCS (Squall line) have subtypes including leading stratiform, parallel stratiform and trailing stratiform. A system's cold pool usually controls the overall propagation speed line.

The Skew-T/log p diagram: Lines and what they represent, Forecast uses, Mandatory levels, Profile types (Loaded Gun, Inverted V etc.) and the weather associated with them

The Skew-T/log P diagram includes pressure grid lines, temperature grid lines, dry adiabats, moist adiabats, and mixing ratio lines. Mandatory levels include the lifted condensation level (bottom of cloud base), level of free convection (level where parcel gains positive energy and can rise freely until it reaches capping inversion), convective condensation level (height of cloud base if parcel is only rising due to positive buoyancy) and equilibrium level (where parcel is colder than environment again). Loaded Gun sounding has low LCL and LFc, an inversion present, dry air aloft and short/fat CAPE. It produces large hail, tornadoes and convective wind gusts greater than 58 mph. The dry microburst or inverted v sounding occurs due to evaporation below the LCL, If the LCL is below freezing, the initial precipitation will be snow. The "mean Ohio thunderstorm" sounding has saturation throughout the entire atmosphere with a tall skinny CAPE. The "wet microburst" is forced by mid-level entrainment of dry air and precipitation loading with steep lapse rate below the LCL and high precipitable water values.

Be able to describe the steps in the classic persuasion model and the general model of risk communication

The classic persuasion model is as follows: source -> message -> channel-> receiver->effect-> feedback -->**repeat**. The general model of risk communication is: hear-> confirm->understand->believe->personalize-> and respond. Receiving is using sensory abilities (hearing, seeing, smelling, feeling) to recognize new information. Understanding is attaching meaning to the information. It is better if It is specific about the hazard, repeated over multiple channels, from official sources and if confirmed. Believing is the cognitive acceptance that understanding is correct. The message conditions are similar to understanding including consistent, repeated, official and confirmed. Trust is also a component. It can be specific or general. Personalization is the acknowledgement that one might be personally affected. The response is actions taken including confirmation of the message which also depends on the demographic information, pre-event perceptions and social networks.

Be able to list and discuss common disaster myths. How do they come about? Which have some truth?

The cry wolf effect is the belief that if you forecast something wrong, people not listen later; however, they will. If they evacuated once then they're likely to evacuate again. Another myth is price gouging which is a price mark up. But the truth is most states have laws against it, ex gas. Another myth is that dead bodies from disasters lead to epidemics; however, sanitation is usually readily present so not the case. There also a myth of extreme trauma and shock following disaster which can be true for some people who have seen dead or large scale destruction or have loved ones die.

General circulation Hadley and Walker circulations Seasonal flow patterns and conditions

The general circulation is described by the earth's desire to reach thermal equilibrium through the transport of thermal energy (ie. Heat) through the Earth by heat transfer from the surface to the atmosphere by convection and the heat transfer from the tropics to the poles by advection. The firs tis a vertical energy gradient and the second is latitudinal energy gradient. The excess energy that is at the surface is transported through sensible and latent heat fluxes. Hadley circulation is the meridional circulation with an ascending branch in the low latitudes and a subsiding branch in the subtropics. The ascending branch is at the meteorological equator which is at 5°N. This line is formed by the imbalance of land and water in the North Hemisphere and Southern Hemisphere. The Pacific Walker circulation is associated with rising motion in the western Pacific near Indonesia and subsidence in the eastern Pacific off the west coast of Central and South America. This leads to cool, dry conditions along the coast of Peru and warm, wet low pressure near Australia.

The Hodograph: Uses, What is plotted and how it is plotted, Shapes (hook, straight lines) and storm morphology

The hodograph is a 2D representation of a 3D wind. Each layer is plotted as a point according to its wind speed and direction. You can use it to calculate storm motion with the average 0-6 km winds, 700 mb winds or the bunkers method. You can also use it to calculate the storm relative helicity. It is similar to CAPE but is for wind. The larger the SRH the better. Different shapes include the pulse storm (low magnitude turning and struggles with organization), straight hodograph (causes storm to split into left and right) and clockwise hodograph.

Supercells: Lemon Model

The lemon technique is used to determine the type and severity of the storm. It is done within stages. In step 1, the storm has a tilted updraft. There are radar echoes on each level. Below the top of the storm, we see the highest reflectivity. Look at the 0-6km wind or 500 mb wind to determine storm motion. In stage 2, updraft is more tilted which means storms maturing. You start to see hail and precipitation forming downwind. The radar echoes are elongating in the direction of the mean wind. At this point, likely to see mesocyclone. The motion will likely slow down and turn to the right. We will likely see the weak echo region on the back side of the storm. In stage 3, updraft is nearly vertical up to 60,000 feet. This means the storm is almost about to end but really strong. This is when the BEWR is visible and large hail/tornadoes. The v-notch helps to determine the stage difference.

Hail: Formation/Growth, Climatology

The main ingredients of hail formation is cumulonimbus cloud, high liquid water content, a strong and sustained updraft and hailstone embryo. Hailstone growth occurs due to the collision-coalescence process. Depending on temperature, there is wet growth, spongy growth and dry growth. The wet growth is when supercooled droplets collide with hailstone embryos. Spongy growth is similar to wet growth except the hailstones retain all collected supercooled water which then freezes, so there are air bubbles trapped in a frozen layer. Dry growth is when any of the supercooled water or ice crystals that collide with the hailstone are accreted. Maximum hail event in CONUS is in Wyoming, Colorado and New Mexico.

Hypothesis testing (parametric) T-tests F-tests Chi-squared tests

The null hypothesis is opposite of what is the desired outcome of the test. Types of null distributions include the t distribution for a test on means, the f distribution for a test on variances and the chi square test which is a test on distribution shapes. If your data sample lies in the improbably region based on the rejection level, reject the hypothesis. 1%, 5% and 10% are common rejection levels and 99%, 95% and 90% are confidence levels. Type 1 error is when you falsely reject the null and type 2 error is when you don't reject it but should have. The one sample t-test is one of the parametric tests and tests that a sample was drawn from a population with a specified mean. The two sample t-test allows you to test the differences of means for two different samples. For a t-test and f-test, the data must be normally distributed. The F tests the variances of two different samples to see if they are similar or different. Chi-square test tests the goodness fit for different hypothetical distributions. The test is essentially comparing histograms.

Be able to describe spatial patterns of extreme weather impacts such as lightning, tornadoes, or hurricanes. What role does population have in damage and deaths?

The ranking of weather deaths high to low is: heat, tornado, hurricane, flood, and wind. The average number of hurricane deaths per year is 47 based on 30 year data, mostly in the south/southeast. There are 800-1400 reported tornadoes per year but only a small percentage that cause casualties. That number is decreasing, almost half the fatalities in mobile homes, more nighttime fatalities than nighttime tornadoes would suggest poor or at a greater risk. The south is most vulnerable. Flooding deaths are not decreasing. Majority occur in vehicles. The most occur in TX, PA, SD, CA and VA. Extreme heat and cold can also result in death, but black people are more impacted. Lightning has the most frequent deaths in Florida with them peaking in summer and over the weekend and mostly male. The reduction in death Is attributed to better forecasts, awareness and better treatment. Almost none occur on the west coast. Most events are becoming less deadly except heat and flash floods. Most events are becoming more costly but this is because greater population or concentrations of wealth and not an increase in events. The higher the population of an area, the higher the cost, death and damage.

What is scale factor? Know some examples.

The scale factor is the ratio of local scale to principal scale. When you move away from the target point, the scale factor is greater than 1. For the transverse mercator projection the scale factor is at the central meridian.

Be able to describe the scientific process and distinguish it from other ways of knowing

The scientific process is a human endeavor (done by individuals), logically and systematically applied, (requires the systematic collection of data), involving ideas and empirical evidence and to evaluate and create knowledge. Other ways of knowing include aesthetics which is related to the philosophy of arts, humanities/critical reasoning and theology/law.

Vorticity advection

There is a vorticity maximum at the base of a trough. There is positive vorticity advection downstream of the trough and there is negative vorticity upstream of the trough. The positive vorticity advection leads to upward vertical motion. The negative vorticity advection leads to sinking air.

Supercell ID and types

There is the classic, low precipitation and high precipitation supercells. Classic supercells have a tight reflectivity gradient on the inflow side of the storm, bounded weak echo region, hook/pendant, inflow notch, rotation couplet and v-notch. HP have a kidney bean shape and a velocity couplet.

The 3 Synoptic Air Streams and their contribution to severe weather

There is the low level air stream from 925 to 850 millibars, the midlevel airstream from 925 or 850 to 700 millibars, and the upper-level airstream from 300 to 200 millibars. Low level airstreams provide latent and sensible heat. Mid-level airstreams provide warm and dry intrusion from the Mexican Plateau and provides a CAP allowing instability to increase. Upper-level airstreams provide a lifting mechanism and a mass evacuation. Classic supercells are found at the base of trough in Mexican plateau in mid-levels, of jet stream and where low level winds are pushing in from the Gulf. HP are in the deep south where low level from Gulf, trough digs into Gulf at the mid-levels, and jet stream lowers across CONUS. The LP has the low level moisture from west of Gulf, trough digging over southern California at mid-levels, and the jet stream is across the middle of CONUS.

Be able to identify severe convection and associated threats via satellite imagery

Thunderstorms are going to be cold and bright on IR and VIS. The shape is based on winds. Overshooting tops are also a useful indication of a thunderstorm. This is when rapid rising motion at the center that extends above the cloud smooth area and looks lumpy. Shadows are another hint. A thunderstorm in a weak shear environment is going to appear like a glob and not stretched out.

Classification (including all contingency statistics)

Using a classification approach rather than a regression equation. Regression Estimate of Event Probabilities (REEP) uses a traditional linear regression formula but requires a class as the predictand. Logistic regression is the logit of a linear regression function. The contingency table will help to compare observed versus forecast. You can calculate from this the percent correct, hit rate (correct yes to total number of yes), probability of false detection (number of false alarms to number of no observations), false alarm ratio (number of false alarms versus the total number of times a yes Is predicted), critical success index (percent correct yes forecasts after correct no forecasts are removed), bias (number of yes to number of no), true skill score (measure of success of forecast to what it would be by chance), heide skill score ( same as TSS but doesn't assume distribution are the same).

Energy

Total energy is equal to the kinetic energy and potential energy sum. A system is subject to external forces other than gravity including internal and external energy.

Types of transformations

Transformation is when a system goes from initial state to final state. This can be adiabatic, isobaric, isothermal or isochoric. Cyclic transformations can be reversible or irreversible but really just go back to initial state like a hurricane. Quasi-static process goes through multiple equilibrium states. There is no real example of a cyclic transformation.

Tropical cyclone definitions and categories

Tropical cyclone is a warm-core, non-frontal synoptic scale cyclone that forms over the tropical or subtropical oceans. Tropical wave is a trough or area of cyclonic curvature in the trade winds or equatorial westerlies. Tropical disturbance is a persistent non-frontal system of organized convection forming over the tropical or subtropical oceans. Tropical depression is a tropical cyclone in the North Atlantic or North Pacific that has maximum sustained surface winds of less than 34 knots (39 mph). Tropical storm is a TC in the North Atlantic or North Pacific that has maximum sustained surface winds of between 34 and 63 knots. Hurricane is a TC in the North Atlantic or Eastern Pacific that has a maximum sustained surface winds of at least 64 knots. Typhoon is a TC in northwest Pacific with maximum sustained surface winds of between 64 and 129 knots. Super typhoon is a TC in the northwest Pacific with maximum sustained surface winds of over 130 knots.

Moment statistics (variance, standard deviation, skewness, kurtosis)

Variance and standard deviation are measures of spread about the mean. Variance is standard deviation squared. Skewness describes the tails of the shape of the spread. Negative is a left tail. Kurtotsis describes flatness/sharpness. '3' is the normal distribution. Less than 3 is flat and higher than 3 is peaked.

Know in detail the difference between vector and raster data models. What is topology and why is it important to GIS?

Vector data represents items as point, linear polygons. Lines have a length characteristic and a polygon has an area and perimeter characteristic. Vectors are advantageous because they have topology. This is the explicit statement of telling the program where the polygon /line/point relationship is. Nodes are endpoints and lines are arcs. Raster outputs a matrix data with grid cells so its better for showing temperature gradients or elevation maps. Each object is represented in a layer as a coding of grid cells. This is not as nice looking and requires you to save a lot of data.

Thermal advection

Warm air advection would leads to rising motion because warm is more buoyant than cold air and it will continue to rise. Cold air advection leads to sinking motion because cold air is more dense.

Where does uncertainty in weather information come from? What are deterministic and probabilistic forecasts? Be able to provide examples of uncertainty and both types of forecasts.

Weather is not an exact science. Origins of uncertainty include atmosphere, observations, models, forecasts, human error. Deterministic is a one-solution value forecast like a high temperature. A probabilistic forecast integrates uncertainty like a 10% chance of rain.

How does seasonal weather influence the economy? What sectors are sensitive to weather fluctuations?

When people are determining how to react to weather, they would consider possible economic losses Sectors directly impacted by weather include agriculture, transportation, and energy resources. The ocean/proximity to water drives the economy and there are more major cities along the coast. A more densely populated area leads to more economic losses when natural disaster strikes.

Jet Streaks

Within the jet stream, there is a jet streak that is a localized even stronger area of wind speeds. The jet streak is not advected but can be regenerated by a strong thermal gradient. As a parcel moves through the jet streak, it is going to respond to PGF and Coriolis force. The PGF is immediate but the Coriolis force is delayed so it will go from geostrophic to ageostrophic at times. Right entrance and left exit is where divergence occurs aloft. The LLJ is forced to rise in the right entrance region and hits area of convergence which forces it to sink. This is the direct circulation. The LLJ is forced to go under the convergence then rise and sink so this is the indirect circulation. There is cold air over warm air which helps to generate an unstable atmosphere. There is PVA where there is divergence aloft.