NASA-IMPACT datashare program

Phenomena

Transverse Cirrus Bands

Transverse Cirrus bands are irregularly spaced bandlike cirrus clouds that form nearly perpendiular to the axis of maximum wind speed in a jet stream. While the cause of their formation is currently unknown, transverse cirrus bands tend to be collocated with atmospheric phenomena that are known to exhibit vertical and horizontal wind shear. Thus, transverse cirrus bands can identify regions where flight-level winds may be turbulent for air travel.

Data Description:

1. Folder Structure:

 transverse_bands/
     |> yes
        |> <images> (1901 images)
     |> no
        |> <images> (4901 images)

2. Data type: images, jpg

You can download the files using: aws s3 cp --recursive s3://impact-datashare/transverse_bands . --no-sign-request/.

High Latitude Dust

Dust aerosols in the atmosphere are known to modulate environmental conditions and the climate system through direct and indirect effects between the land–atmosphere–ocean system. High latitude dust (HLD) is defined as ”particles that are lifted from a surface and travel by suspension in the atmosphere”. Typically, these dust particles are of the range of tenths of μm or larger in size. In addition, dust events are considered high latitude when they are ≥ 50◦N and ≥ 40◦S. HLD tends to occur in specific conditions and is seasonally dependent. HLD events can last anywhere from several hours to several days.

Data Description:

1. Labeled events are stored in a folder with the following structure (214 shapefiles):

 high-latitude-dust_<date>_<id>:
   |> high-latitude-dust_<date>_<id>.dbf
   |> high-latitude-dust_<date>_<id>.prj
   |> high-latitude-dust_<date>_<id>.shp
   |> high-latitude-dust_<date>_<id>.shx

2. Images to be downloaded using GIBS. (https://gibs.earthdata.nasa.gov/wms/epsg4326/best/wms.cgi?SERVICE=WMS&REQUEST=GetMap&layers=MODIS_Aqua_CorrectedReflectance_TrueColor&version=1.3.0&crs=EPSG:4326&transparent=false&width={}&height={}&bbox={}&format=image/tiff&time={}) 2.a. Variables required:

   width = width of the image height = height of the image bbox = [left_latitude, left_longitude, right_latitude, right_longitude]

Note: Use the following for approximate width, height calculation and url generation.

URL = "https://gibs.earthdata.nasa.gov/wms/epsg4326/best/wms.cgi?SERVICE=WMS&REQUEST=GetMap&layers=MODIS_Aqua_CorrectedReflectance_TrueColor&version=1.3.0&crs=EPSG:4326&transparent=false&width={}&height={}&bbox={}&format=image/tiff&time={}"
KM_PER_DEG_AT_EQ = 111.


def calculate_width_height(extent, resolution):
    lats = extent[::2]
    lons = extent[1::2]
    km_per_deg_at_lat = KM_PER_DEG_AT_EQ * np.cos(np.pi * np.mean(lats) / 180.)
    width = int((lons[1] - lons[0]) * km_per_deg_at_lat / resolution)
    height = int((lats[1] - lats[0]) * KM_PER_DEG_AT_EQ / resolution)
    print(width, height)
    return (width, height)


def modis_url(time, extent, resolution):
    width, height = calculate_width_height(extent, resolution)
    extent = ','.join(map(lambda x: str(x), extent))
    return (width, height, URL.format(width, height, extent, time))

You can find the example notebook here

You can download the files using: aws s3 cp --recursive s3://impact-datashare/hld . --no-sign-request.

Cloud Streets

The organization of cumulus clouds into elongated rows oriented parallel to the mean boundary layer flow is a phenomenon often referred to as cloud streets. Organized cumulus cloud streets are the visual manifestation of underlying boundary layer roll circulations commonly referred to as horizontal convective rolls. Formation of boundary layer rolls is attributed to two instability mechanisms – thermal and dynamic instability.

Direct impacts of cloud streets are fairly minimal as they typically do not precipitate or have meaningful environmental impacts aside from surface radiation. The effects of cloud streets are most notable in the presence of sea breeze circulations as intersections of roll circulations and sea breeze circulations are known to force convective initiation. Coastal convection is a primary source of precipitation in these settings and can grow upscale to propagating mesoscale convective systems that modulate the regional and even global precipitation budgets.

1. Folder Structure:

 Cloud Streets/
     |> yes
        |> <images>
     |> no
        |> <images>

2. Data type: images, jpg

You can download the files using: s3://impact-datashare/cloudstreet . --no-sign-request.

Tropical Cyclone

Tropical cyclones are one of the most impactful meteorological phenomena observed on Earth. Tropical cyclones are defined as intense, synoptic scale storms, originating over warm tropical waters characterized by low pressure, high winds, and heavy precipitation. The combination of impacts from heavy wind and precipitation can cause widespread damage and flooding resulting in billions of U.S. dollars of assistance for impacted regions.

1. Folder Structure:

 hurricanes/
     |> <year>
        |> <basin>
            |> <hurricane_code> (naming convention:  <stormid>_goes<13/16>_<YYYYMMDDTHHMMSS>_<intensity>_<lat centroid>_<lon centroid>.jpg)

2. Data type: images, jpg

You can download the files using: aws s3 cp --recursive s3://impact-datashare/hurricanes . --no-sign-request.

Smoke

Smoke is a mixture of gases and particles released in response to the combustion of living or dead biomass. Anthropogenic combustion emissions (such as from power plants or from fossil fuel rig flaring) may also be considered smoke. The exact combustion of smoke is highly dependent upon the fuel, ambient atmospheric chemical composition and meteorological (or physical) conditions.

Here the dataset is a tif file which contains 6 bands from GOES satellite data. You can use rasterio or rio or gdal or xarray packages to read the data.

1. Folder Structure:

 smoke_labeled/
     |> time-<timestamp>-loc-<west_south_east_north>.bmp
     |> time-<timestamp>-loc-<west_south_east_north>.tif

2. Data type: images, bmp, tif

You can download the files using: aws s3 cp --recursive s3://impact-datashare/smoke_labeled . --no-sign-request.