Applications

The aforementioned capabilities have been used to create a number of applications with these and other data sets.

Peru_Rainfall

This program utilizes a daily collection of rainfall observations from northwestern Peru before, during and after the "great" El Nino of 1982 and 1983. There is a network of 66 stations, for which observations are available from November 1, 1982 through June 30, 1983. In addition to days when there are no rain, there are also days with no data available. They are NOT the same. The notion of data invalidity is employed to distinguish them.

Both continuous and discrete realization techniques are provided. For the continuous techniques (e.g., contouring, imaging), the data are gridded to a uniform, regular grid via weighted averaging. The discrete techniques (e.g., scatter plots) may be overlaid with the continuous ones. Optionally, the elevation of each rainfall station may be used to create a topographic surface, that is overlaid with a pseudo-color representation of the rainfall. The daily distribution of the rainfall at an individual station may be shown as a time history plot.

Rainfall Realization Control Panel: The rainfall data may be gridded and shown as a two-dimensional or three-dimensional pseudo-colored surface. Regions where data are not available are shown as a gray wireframe mesh. Black or pseudo-colored iso-contour lines may be overlaid on the rainfall surface. Alternatively, pseudo-colored filled contours may be displayed. The contour increment is 20 mm of daily rainfall, the major tick mark increment on the pseudo-color bar. The locations of the actual stations that have data may be shown with a pseudo-colored disk or the numerical value.

The data for one day are shown as pseudo-colored deformed surface, where the height of the surface corresponds to local topography. A time history of the rainfall for a single station is shown as a plot.

Gridding Options Control Panel: The weighted averaging of the gridding process of the scattered data may be adjusted. The number of stations used to compute a value at each grid point may be selected. The radius of influence for each grid point may be selected.

Rainfall Time History Plots Control Panel: Optionally, a daily time history plot for the entire 11/1/82 - 6/30/83 period may be shown for a specific station, which is selected by name. The data are shown as a green line. In addition, the location of the station may shown on the map. The plot may be augmented with the daily mean (in yellow) and/or the daily maximum (in blue) for all reporting rainfall stations.

Ordinarily, this region is a desert. During the large-scale thunderstorms that occur as a result of El Nino, several centimeters of rain will fall each day, washing away everything in its path. This can be seen as deep blue regions in the various realizations. The storms are clearly affected by the local topography. The storms originate in the Pacific Ocean. As they reach the foothills of the Andes, they are diverted off to the northwest. A daily animation of these data illustrate this effect. The Sequencer is tied to Julian day for this purpose. The default period is during a major storm that took place in January 1983.

The rainfall realizations are registered with a base map in magenta showing the Pacific coast and part of the Peru-Ecuador border.

The data are available courtesy of the National Space Science Data Center, NASA/Goddard Space Flight Center.

A portion of the visual program that is the implementation of this application is shown.

SAI_CDAW9_EventC

This program provides geographic mapping/viewing of ultraviolet aurorae remotely sensed by the Spin-Scan Auroral Imager on board NASA's Dynamics Explorer-1. The data are from the period 00:00 GMT through 12:00 GMT at irregular intervals (38 images total) on May 3, 1986. This is Event C from the Coordinated Data Analysis Workshop-9 sponsored by the National Space Science Data Center at NASA/Goddard Space Flight Center. The auroral imagery originated at the University of Iowa via Dr. Louis Frank. The data show the emissions during a polar substorm, highlighting the auroral oval. Errors in the geographic registration of the original pixels are evident as streaks across rendered surfaces. Five different map projections are supported with fiducial line as well as world coastline and political boundary overlays. The cartographic projections are implemented via coordinate warping without interpolation. Missing, zero intensity and off-earth data are eliminated and appear as black cells or regions. A two-step linear pseudo-color map to the intensities in kR is employed. It is linear in hue from blue to red for low intensities and red for all high values.

Realization Control Panel: One of five pseudo-colored realization techniques may be chosen: 1) scatter map, 2) image, 3) smoothed image, 4) shaded surface or 5) filled contours. The filled contour thresholds are 2, 4, 6, 8, 10 20, 40, 80 and 120 kR. In addition, histogram equalization (stretches the pseudo-color map and highlights the auroral oval and the sunlight contaminating the sensor), a Sobel filter (simple edge detection) a Gaussian filter (smooths the data), or an erosion operation with a Sobel filter may be applied to the data (separates the auroral oval, mostly).

Cartography Control Panel: One of five geographic map projections may be selected (Cylindrical Equidistant, Mollweide, Mercator, South Pole Orthographic and spherical). The orthographic projection is most appropriate for viewing the auroral oval and the evolution of the substorm. An additional option is available for placing of fiducial lines on the coastline and national boundary map.

One auroral image is shown in a south pole orthographic projection as a pseudo-colored, deformed shaded surface that has been smoothed by a Gaussian filter.

IGRF_1945_1985

This program allows a user to examine the output of an empirical model of earth's magnetic field, the International Geomagnetic Reference Field. It supports user-specified field line tracing, examination of the field strength, etc. through a number of different realization techniques. The data set represents the entire valid range of this model -- temporally: 1945 through 1985 for every year (at January 1) and spatially: the whole earth from its surface to an altitude of 30,000 km. The data were computed at 2.5-degree resolution in latitude and longitude and 2000 km in altitude. The data are presented as collection of geographically-based spherical shells. The model used to create the data is available courtesy of the National Space Science Data Center at NASA/Goddard Space Flight Center.

Magnetic Field (B) Realization Control Panel: The user may choose how the magnetic field data are realized. The vector B-field may be shown as lines or arrow glyphs. The scalar field, |B|, may be shown as a volume or isosurfaces. If the latter, the user may enter value(s) for the surface extraction. The scalar field may optionally be shown as log10(|B|).

Magnetic Field Magnitude (|B|) Plane Control Panel: The user can place an annulus showing |B|, whose normal is determined by the dial widgets. The annulus is psuedo-color mapped and contoured.

Magnetic Field (B) Lines Control Panel: The user may choose how the magnetic field lines are traced. The seed points are entered manually or are computed automatically (20 uniformly distributed in the volume). B, curl B or both may be chosen for the lines to be traced.

Altitude Slice Options Control Panel: Optionally, the user may select a slice of the model at a specific altitude (0 to 30000 km by 2000), and view it as pseudo-color image of |B| or contours (every 0.025) or deformed surface, or streamlines or vector arrows of B. In addition, cartographic projections may be applied with a coastline and political boundary overlay.

The B-field is shown as a translucent, pseudo-colored isosurface at a value of 0.4 Gauss and streamlines advected by a set of coordinates entered manually.

CDAW9_EventC

This program does correlative visualization of data from various sources for the period 00:00 GMT through 12:00 GMT on May 3, 1986 during a magnetospheric substorm (i.e., when there are aurorae) near the South Pole. It shows computed and observed data simultaneously. This is Event C from the Coordinated Data Analysis Workshop-9 sponsored by the National Space Science Data Center at NASA/Goddard Space Flight Center. One data set is the output of an empirical model of earth's magnetic field, the International Geomagnetic Reference Field, which is assumed to be static for the period in question. A second data set is auroral ultraviolet imagery remotely sensed by the Spin-Scan Auroral Imager on board NASA's Dynamics Explorer-1 (DE-1). The auroral imagery originated at the University of Iowa via Dr. Louis Frank.

There are three data sets of ground-based magnetometer observations, which are located at the South Pole, McMurdo Bay and Siple. There are a set of in situ (point) observations (i.e., samplings) of the plasma originating from the solar wind by instruments on board NASA's International Sun-Earth Explorer-1 (ISEE-1). These measurements are of energetic protons (temperature in electron volts, number density and velocity) and the magnetic field. Each of these data sets originally were in different cartesian coordinate systems. All of the data are shown geographically via coordinate warping surrounding a topographically derived globe and are properly registered and converted. The data are at different time resolutions but were interpolated to a common time base of irregularly-spaced 38 steps corresponding to those of the auroral images external to Data Explorer.

The program supports user-specified field line tracing, examination of the field strength, etc. for the magnetic field data through a number of different realization techniques. The time-dependent magnetic field as measured on the ground is shown via color-mapped vector glyphs. The time-dependent ultraviolet emissions of aurorae are shown as color-mapped translucent surfaces warped onto a sphere. Alternatively, the images may be shown as psuedo-color glyphs corresponding to the location of the pixels. This technique is useful since some of the pixels on some images have not been properly geolocated. The radius of the sphere is scaled according the radial distance of the spacecraft from the earth's center. The user can control the relative amount of offset between these spherical surfaces and the globe. These data are quite noisy and regions of no data are visible as open patches. The ISEE-1 data are shown as glyphs. The size of sphere glyph corresponds to the proton density, while its color corresponds to the proton temperature. There are two arrow glyphs, one for the proton velocity and the other for the magnetic field. Both are scaled in size by their respective magnitudes. The proton velocity glyph is magenta, while the magnetic field glyph is pseudo-colored by the same scale as is used for the ground station observations and the static magnetic field model data. The key feature in these images is the auroral oval, a region of intense emissions corresponding to where charged particles follow magnetic field lines into the earth's atmosphere. The interaction of the particles and the atmosphere leads to the observed emissions. Through the time sequence, the pulsating of the aurorae are quite visible. In some images there may be some regions of high intensity independent of the auroral oval. Since the images are taken mostly at night, this is sunlight coming across the day-night terminator and contaminating the observations.

Viewing Control Panel: The user may choose between a smooth or Rubbersheet'd presentation of the globe.

General Realization Control Panel: The user may choose which data set is to be shown and in some cases how it is to be realized. The magnitude of the static B-field may be shown as a volume or via isosurfaces. If the latter, then the user can enter the desired isosurface values. The static B-field may be shown via streamlines or vector arrow glyphs. The UV auroral image may be shown as a smooth surface or the locations of each pixel may be indicated. Since some pixels are not properly geolocated, the latter may be useful. The image "surface" is on a sphere, whose radius corresponds to that of the radial distance of the spacecraft, Dynamics Explorer-1, from the earth and the time the data were taken. The radius may be reduced to allow the other data to be seen more clearly. The in situ B-field observed by ISEE-1 may be shown as a pseudo-colored arrow glyph. The same color map as with the B-field is employed. The in situ proton data from ISEE-1 may be shown. Velocity is indicated by magenta vector arrows. Temperature is indicated by the color of a sphere and the density is indicated by the size of that sphere. The magnetic field as observed from the ground may be shown via pseudo-color-mapped vector arrows.

Magnetic Field Magnitude (|B|) Plane Control Panel: A user can place an annulus showing |B|, whose normal is determined by the dial widgets. The annulus is pseudo-color mapped and contoured.

Magnetic Field (B) Lines Control Panel: The user may choose how the magnetic field lines are traced from a static data set. The seed points may be entered manually through the vector list widget, sampled from the positions of the auroral image of the current time step, or from the constant locations of the ground stations. B, curl B or both may be chosen for the lines to be traced.

All of the data sets are shown, with magnetic field lines from the static field and a pseudo-colored, translucent shell of auroral imagery surrounding the earth. The three ground magnetometers are shown as pseudo-colored arrows while the position of ISEE-1 is shown with a pseudo-colored sphere for proton temperature and density, thick arrow for proton velocity and thin arrow for in situ magnetic field.

stratosphere

This program allows a user to examine gridded, volumetric monthly climatology of atmospheric temperature and geopotential height data for January 1975 through December 1978. The data are at a spatial resolution of 10 degrees over the northern hemisphere from 100 mb to 10 mb. The data are derived from balloon and aircraft observations, which have been modelled and gridded. The data may transformed from the original collection of four stacked two-dimensional grids to a collection of spherical shells or a collection of north pole orthographic disks. The user may examine either via direct volume rendering or surface extraction or pressure slicing for both parameters. For isosurfaces, specific value(s) may be entered. For a slice, a specific pressure level may be chosen. The data optionally may be smoothed prior to realization.

The data are available courtesy of the National Space Science Data Center at NASA/Goddard Space Flight Center.

Temperature Realization Control Panel: The user may choose to view the stratospheric temperature as a pseudo-colored volume, isosurface or slice. For isosurfaces, specific value(s) may be entered. For a slice, a specific pressure level may be chosen. The data optionally may be smoothed prior to realization.

Geopotential Height Realization Control Panel: The user may choose to view the stratospheric geopotential height as a pseudo-colored volume, isosurface or slice. For isosurfaces, specific value(s) may be entered. For a slice, a specific pressure level may be chosen. The data optionally may be smoothed prior to realization.

Stratospheric Viewing Control Panel: The user can choose the view the northern hemisphere volume as a collection of concentric hemispherical shells or as a cylindrical stack of orthographic disks.

Temperature isosurfaces of 195 and 220 K, and geopotential height isosurfaces at 19400 and 23700 m are shown in a northern hemisphere orthographic cylinder.

troposphere

This program allows a user to examine gridded, volumetric atmospheric temperature and wind data. The data are at a spatial resolution of 2.5 degrees over the whole earth from 1000 mb to 100 mb. The data are derived from the spacecraft, balloon and aircraft observations, which have been modelled and gridded. They are on a 2.5 degree grid, originally 144 x 73 cells (longitude x latitude). The data are transformed from the original collection of seven stacked two-dimensional grids to a collection of spherical shells. The data are available daily for October 1, 1987 through October 10, 1987 at 00:00 GMT from the National Space Science Data Center at NASA/Goddard Space Flight Center.

The user may examine either the daily temperature and/or the wind data through a number of different realization techniques. The temperature data may be realized via direct volume rendering, surface extraction, pressure surface or cutting plane with contours, each of which is pseudo-color mapped. One or more values may be chosen for the isosurface. The specific pressure level may be selected, The cutting/mapping plane in this spherical, earth-centered coordinate system is an annulus. A probe is used to select the normal of the annulus, which is marked with an arrow. The wind data may be realized as glyphs, streamlines or ribbons or streaklines or ribbons, which are pseudo-color mapped by horizontal wind speed. The ribbons may be optionally twisted by the curl of the velocity field, which is proportional to the wind vorticity. The user may enter specific seed points for the lines or the number of seed points, which are uniformly distributed in the volume. For glyphs, their size is redundantly mapped to horizontal wind speed. Optionally, the user may choose to realize the three-dimensional horizontal wind speed as a volume, pressure surface or isosurfaces.

Volumetric Temperature Realization Control Panel: The user can choose to realize the temperature data as an annulus, volume, pressure surface or isosurfaces. For the annulus, a probe is used to select the normal and it is pseudo-color mapped and contoured. For an isosurface, the user may enter one or may values for which to extract the surfaces.

Volumetric Wind Realization Control Panel: The user may choose to realize the wind velocity via arrow glyphs, lines or ribbons. In all cases, the geometry is pseudo-color mapped by horizontal wind speed. The ribbons may be optionally twisted by the curl of the velocity field. The ribbons may be derived from either stream or streaklines. The user may enter specific seed points for the lines. Optionally, the user may choose to realize the three-dimensional horizontal wind speed. The user can choose to realize the speed as a volume, pressure surface or isosurfaces. For an isosurface, the user may enter one or may values for which to extract the surfaces.

Pseudo-colored and opacity-mapped temperature isosurfaces at 194K and 285K are shown with streamlines of wind velocity, pseudo-colored by horizontal wind speed on registered with a gray-scale globe in spherical/geographic coordinates.

A user may also choose to create conventional two-dimensional geographic maps of these data for a specific pressure level. The temperature data are realized as a pseudo-color image overlaid optionally with similarly pseudo-color mapped contours. The user has the ability to adjust the boundaries of the pseudo-color map and contouring range as well as the increment of the contour lines. Contouring may be filled or lines. The user may choose between cell-based pseudo-color imaging and smoothed images. In addition, numeric labels may be overlaid on the temperature data. The user also has the option of creating a deformed surface from the temperature data.

The wind data are realized as vector (arrow) glyphs, whose length corresponds to wind speed and direction corresponds to wind direction. The glyphs may be a constant color (magenta) or pseudo-color mapped to the wind speed. The glyphs are rendered on a reduced resolution grid, where the user can control the degree of reduction. Alternatively, the wind data may be realized as streamlines, where each time step is considered steady-state. The streamlines may be a constant color or pseudo-color mapped to the wind speed. The program supports five different cartographic map projections, which are implemented without interpolation via coordinate warping. The projections are Cylindrical Equidistant, Mollweide, Mercator, northern and southern hemisphere orthographic, and spherical. The data are overlaid with conventional maps of world coastlines and political boundaries as well as fiducial lines.

Pressure Slice Viewing Options Control Panel: The user may choose which pressure level in the atmosphere to study with two-dimensional techniques. The temperature data are realized as a pseudo-color image overlaid with similarly pseudo-color mapped contours. The user may select the upper and lower bounds for the color scale and contouring as well as the contour increment. The contouring may be line or filled. In addition, numeric labels may be overlaid on the temperature data. The user may choose between cell-based pseudo-color imaging and smoothed images. The horizontal wind data are realized as vector (arrow) glyphs, whose length corresponds to wind speed and direction corresponds to wind direction. The glyphs may be a constant color or pseudo-color mapped to the wind speed. The glyphs are rendered on a reduced resolution grid, where the user can control the degree of reduction. Alternatively, the wind data may be realized as streamlines, where each time step is considered steady-state. The streamlines may be a constant color or pseudo-color mapped to the wind speed. The program supports five different cartographic map projections, which are implemented without interpolation via coordinate warping. The projections are Cylindrical Equidistant, Mollweide, Mercator and northern and southern hemisphere orthographic, and spherical. The data are overlaid with conventional maps of world coastlines and political boundaries as well as fiducial lines. The user may choose the particular style of map that is employed for realization. These options, include the map projection, the use of and style of fiducial lines, and the map color.

Pseudo-color-filled contours every 10 K are shown on Mercator map with streamlines of horizontal winds pseudo-colored by speed at the 1000 mb level.

ozone

This program illustrates the results of the reduction in total ozone observed annually during the Antarctic spring and shows daily data as observed globally by the Total Ozone Mapping Spectrometer (TOMS) on NASA's Nimbus-7 spacecraft, which is in a (polar) sun-synchronous orbit. The TOMS instrument was operational from late 1978 to May 1993. It measured the total column density of stratospheric ozone by observing backscattered solar ultraviolet radiation in seven spectral bands. Approximately 200,000 such measurements were made each day, which covered the entire globe. These data can be used to study the formation of the so-called ozone hole and its morphology. It should be noted that the term ozone hole is a misnomer. It is actually a depletion, which can be seen as a blue region or depression in the surface realizations. Since the instrument requires sunlight to operate there will be periods of missing data due to local polar winters in addition to the usual data dropout problems with spacecraft observations. These regions are visible as gaps in the surfaces. They are NOT the ozone hole. The data have been gridded in a regular lattice of 180 (one degree in latitude) x 288 (1.25 degree in longitude) from the raw observations for daily global coverage. The total stratospheric ozone measurements are in terms of Dobson Units (DU) ranging from about 100 to 650 (i.e., the minimum-maximum range for the entire data. One Dobson Unit corresponds to a column density of 2.69 x 10^16 molecules of ozone cm-2.

This program provides analysis of daily total column global ozone for the period September 1, 1987 through November 30, 1987, which are available courtesy of the National Space Science Data Center at NASA/Goddard Space Flight Center. It supports conventional two-dimensional geographic mapping, for which the data are realized as a pseudo-color image optionally overlaid with similarly pseudo-color mapped contours. The user has the ability to adjust the boundaries of a pseudo-color map, which defaults to a non-linear RGB color map and contouring range as well as the increment of the contour lines. The program supports five different cartographic map projections, which are implemented without interpolation via coordinate warping. The projections are Cylindrical Equidistant, Mollweide, Mercator, northern and southern hemisphere orthographic and spherical. The data are overlaid with conventional maps of world coastlines and political boundaries as well as fiduical lines.

From the choice of two-dimensional projection each day of data may be realized as a deformed surface, which is redundantly represented by both the pseudo-color spectrum and height. The height mapping clearly dramatizes the concept of a hole or depression in the ozone layer while the color enhances this perception as color would enhance the topographic map. The daily sequencing of the data showing the (super)rotation of the ozone hole surrounded by the ozone ridge region, which is consistent with the formation of the polar vortex that some believe help to trap ozone-destroying chemicals in the stratosphere and thus, aid in the creation of the Antarctic ozone hole. Such rotation usually has a period of several days. Below each translucent surface is a world coastline map in magenta with political boundaries corresponding to each hemisphere. The map is from a data base of lines, which has been transformed in a manner similar to that of the ozone data.

This program permits geographic/spherical browsing of daily total column global ozone by carrying the cartographic theme to a three-dimensional continuous surface by performing a cartesian to spherical coordinates transformation. By default the ozone is triply redundantly mapped to height (now radial), color and opacity so that high ozone values are thick, far from the earth and reddish while low ozone values are thin close to the earth and bluish. However, the capability to select any of these mappings independently is available. Replacing the map is a globe in the center of the ozone "asteroid", which is created by an appropriately color-mapped topographic data base on a rectilinear grid, which is similarly warped to a smooth or deformed sphere.

Independent of the specific realization techniques, the user can examine the daily data, the difference from one day to the next, a running difference from a base day, or the deviation of the daily data from the corresponding monthly mean. On any of these choices of data, the user has the option of applying histogram equalization, various signal processing techniques (e.g., edge detection) or select a longitude value for viewing a zonal profile plot of the ozone.

The ozone data for the southern hemisphere are shown as a deformed, pseudo-color-mapped surface in an orthographic map projection with a zonal profile plot along the Prime Meridian.

Geographic Centroid for Value Control Panel: The user may precisely select the latitude and longitude of the geographic centroid for extracting a value or creating a zonal slice. The actual ozone value at that location is reported in the main image and a marker is indicated for that location on the ozone surface.

Realization Control Panel: The user may select from 2, 2-1/2 or 3d realization techniques for these 3d data. The user may control the range of values to be realized. Optionally, a zonal profile plot may be shown. The zonal slice is taken at the longitude of the value extraction centroid. The user may choose among several color maps including a linear RGB, non-linear RGB and gray-scale.

"Asteroid" Options Control Panel: If 3d (spherical) realization is chosen, the user had the option of showing a smooth or radially deformed spherical shell and whether the color of the shell is constant or pseudo-color. In either case, the opacity is mapped to the ozone value. A colored or gray-scale globe may be selected as well as whether the globe is smooth or radially deformed.

2 and 2-1/2-Dimensional Options Control Panel: For flat representations, the user may select from pseudo-color images, contours, image and contours and filled contours. An increment in DU may be chosen for contours. Line contours may be black or pseudo-colored. The actual values may also be indicated. The contour increment option controls the frequency of the labelling. If flat or surface realization techniques are chosen, then the user may select the geographic map projection, the width of the map and whether fiducial lines should be shown.

Analysis Options Control Panel: The data to be visualized may be the original data. Optionally, histogram equalization, a Sobel filter or a Gaussian filter may be applied. For "flat" surfaces, the data may be viewed in a smoothed or cell-based fashion. The data are derived from the daily grids. Optionally, diurnal differences, running differences from a specific day, or the deviation of the daily data from the corresponding monthly mean may be selected. A threshold value may be entered, below which the corresponding area of the earth's surface is calculated. This can be used to estimate the areal extent of the ozone depletion region. The result is reported in the main image window.

The data are shown as a pseudo-colored spherically warped surface with a zonal plot at 60 degrees east longitude after being histogram equalized.

vortex

This program provides a view of the south polar vortex by comparing global total column ozone with 100 mb temperatures and horizontal winds for September 1, 1987 through November 30, 1987 on a daily basis. Refer to the program entitled ozone for more information about the ozone data and the visualization techniques used. Atmospheric temperatures at the level in the atmosphere in which the pressure is 100 mb, which is below the tropopause may be realized using the same techniques as the ozone (psuedo-color image, contours or deformed surface). The data ranging from 180 to 235 K. Above the orthographic plate of temperature is a similar plate of vector glyphs which correspond to the horizontal winds at the 100 mb level. The size of the vector glyphs and the color correspond to wind speed, which ranges from 0 to 80 m/sec. In addition, the scalar techniques used with the ozone and temperature may be optionally applied to the wind speed. The resultant geometries are stacked vertically to permit correlative visual comparisons.

As one sequences through September, coming out of Antarctic winter, the availability of polar ozone data is apparent as well as the formation of the hole. Precursor and correlative signatures are visible in the temperature data and the wind patterns evoke a cyclonic pattern corresponding to the polar vortex. The 100 mb data are derived from the spacecraft, balloon and aircraft observations, which have been modelled and gridded. The 100 mb are on a 2.5 degree grid, originally 144 x 73 cells (longitude x latitude). The program supports four different cartographic map projections, which are implemented without interpolation via coordinate warping. The projections are Cylindrical Equidistant, Mollweide, Mercator and northern and southern hemisphere orthographic. If the south pole orthographic projection is selected this correlation corresponding to the vortex is quite clear in each data set.

Viewing Control Panel: The user has the ability to select which of five data sets to display, total column ozone, 100 mb temperature, 100 mb horizontal winds, topography and a map of coastlines and national boundaries. The user can choose the geographic map projection to use. The ozone, temperature and wind may be stacked and registered with the maps or may be viewed separately in separate windows with the coastlines map.

Realization Options Control Panel: There are a few options for the realization of each data set. The ozone and the 100 mb temperature can be shown as a flat (i.e., image) or deformed surface, which is pseudo-colored. If flat, then the option of showing contours every 50 DU for ozone and every 10K for temperature is available. The contours may be line or filled. The 100 mb wind speed may be shown in the same way as the ozone and temperature, where contouring is every 10 m/sec. Alternatively, the wind velocity may be shown as speed-colored vector glyphs or streamlines.

Model Ozone, Temperature and Wind Data Control Panel: The user may compare the ozone, temperature and wind (speed) data by forming a simple model relating the parameters. This model is a linear combination of the three parameters and looking at the results (i.e., A*ozone + B*temperature + C*wind). Each of the three parameters are normalized (i.e., the values range between 0 and 1 and the weights for each are between 0 and 1. The weights may be adjusted through separate interactors. The resultant combination may be viewed as a pseudo-colored image, contours or deformed surface.

Ozone as a pseudo-colored deformed surface, winds as pseudo-colored vector arrows and temperature as a pseudo-colored disk with contours are shown in a south pole orthographic projection. The model output as a pseudo-colored deformed surface is also shown in a south pole orthographic projection.

ISCCP

This program supports the viewing of monthly averages ofseveral global cloud parameters from July 1983 through June 1988 from the C2 data sets of the International Satellite Cloud Climatology Project (ISCCP). The original data are accumulated from the monitoring of the earth's atmosphere from five geostationary spacecraft (METEOSAT, INSAT, GMS, GOES-East and GOES-WEST) and at least one polar orbiting NOAA spacecraft. The data are on 2.5 degree grids, nominally at a 250 km resolution. These data can be used to infer the global distribution of cloud radiative properties and their seasonal variations. They have the potential to improve the understanding of the effect of clouds on climate and radiation balance. The data are available courtesy of NASA/Goddard Space Flight Center. This program supports the viewing of the twelve parameters available, including cloud top temperature and pressure, the optical depth of cloud deck, surface temperature and the amount of clouds observed, etc. The data are presented via cartographic techniques with the capability of viewing up to four simultaneously. Any of the parameters may be independently realized via pseudo-color imagery, contours, surface deformation and numeric values.

Realization Control Panel: The user has the ability to select the display and options associated with each realization function that may be mapped to a specific data set. For pseudo-color imagery the data may be smoothed and/or histogram equalized. For contours, the contour increment can be chosen and the lines may either be black or pseudo-colored.

General Control Panel: The user may choose one of 12 parameters to be independently realized as a pseudo-color image, contours, deformed surface, or numeric values. In addition, the user can select whether annotation should be shown in the image. Optionally, zonal and meridional plots of the parameter selected as a pseudo-color image may be created if a cylindrical equidistant map projection is being employed. The points to be plotted are selected via a ProbeList (in the Cursors View Control mode of the Image window). The values at those points and a line connecting them are shown on the pseudo-color image.

Cartography Control Panel: These atmospheric data may be presented using cartographic techniques. The user has the ability to select a map projection and whether or not fiducial lines are to be displayed. If fiducial lines are to be placed on the map, then the increment in degrees can be specified.

Cloud top temperature as pseudo-color, surface (clear sky) surface temperature as pseudo-color contours and percent cloudiness as numerical labels are shown in a Mollweide map with global coverage.