3D View of Super Typhoon Nepartak from the ISS – July 7, 2016

"Nepartak had winds of 265 kph (165 mph) making it the equivalent of a Category 5 storm on the Saffir–Simpson scale earning it the designation of “Super Typhoon”"

One of the precursor projects for Tropical Weather Analytics’ Hurricane Hunter Satellites was the CyMISS (Tropical Cyclone intensity Measurements from the ISS) project which ran from 2014 to 2019. Funded by a series of grants from CASIS (Center for the Advancement of Science in Space) which manages the ISS US National Laboratory for NASA, CyMISS was performed by the science team at Visidyne (the corporate antecedent of Tropical Weather Analytics) for NASA’s Tropical Cyclone Experiment as part of NASA’s CEO (Crew Earth Observations) activities on the International Space Station. The goal of CyMISS was to acquire image sequences of intense tropical cyclones (TCs), such as hurricanes and typhoons, from the ISS using a specially designed photography protocol (see “The Cyclone Intensity Measurements from the ISS (CyMISS)”) to support the development of stereographic imaging techniques of these destructive storms. These techniques will allow the altitudes of the cloud tops near the eye of TCs to be precisely determined so that these TCs can be more accurately characterized compared to existing remote sensing methods (see “Using the Carnot Engine Model to Characterize Hurricanes from Orbit”). Because of how these stereo images are acquired, processed, and analyzed, the motion of cloud features can also be tracked to derive the winds in three dimensions including unique measurements of vertical winds – a vital input for accurately modelling the future track and intensity of TCs (see “The Impact of New Satellite Wind Measurements on Hurricane & Tropical Cyclone Forecasting”)

During the course of this five-year project, the CyMISS project science team (which is now the core of the TWA science team) amassed a large collection of storm images that we wish to share. One of the TCs observed in support of CyMISS by the crew of ISS Expedition 48 was Super Typhoon Nepartak off the coast of Taiwan on July 7, 2016.

This is one of the original color photographs (ISS048-E-22717) of Super Typhoon Nepartak taken by the crew of the ISS at 05:21:44 GMT on July 7, 2016 in support of CyMISS. Click on image to enlarge. (NASA/JSC)

A total of 299 photographs, like the example shown above, were acquired of Super Typhoon Nepartak by the crew of ISS Expedition 48 on July 7, 2016 during a five-minute observation session which started at 05:19:00 GMT (see “ISS Daily Summary Report – 07/07/16”). At this time, the eye of Nepartak was located at about 14.1°S, 53.3°E some 260 kilometers east-southeast of the southern tip of Taiwan. Nepartak was beginning to weaken as it interacted with the island but had winds of 265 kph (165 mph) making it the equivalent of a Category 5 storm on the Saffir–Simpson scale earning it the designation of “Super Typhoon Nepartak”. Only a few hours after these images were taken, the eye began to breakup and fill with clouds as the storm continued to weaken due to interactions with land. A synoptic 2D color view created from a subset of the ISS photographs taken that day is shown below. In order to create this mosaic, the individual photographs from the original image sequence were remapped to approximate an overhead view before the frames were stitched together into a synoptic view covering an area of approximately 2,100 by 900 kilometers. A high-resolution version of this 2D mosaic with an image scale of ~800 meters/pixel can be viewed by clicking on the image below.

This mosaic shows Super Typhoon Nepartak as viewed from the ISS on July 7, 2016. It was created by remapping the original 299 photographs taken by the crew of the ISS to approximate an overhead view before stitching them together and covers an area of 2,100 by 900 kilometers. Mainland China is visible in the left end of the image. Click on the image to view a high-resolution version with a scale of about 800 meters/pixel. (TWA/JSC-NASA)

The close-up 3D image shown below was created using a pair of photographs of the 43-kilometer eye of Super Typhoon Nepartak taken a few seconds apart around 05:22 GMT. Only the red channel of the original color images was used in order to cut through any atmospheric haze and maximize the visibility of the cloud features. These images were remapped to approximate an overhead view before being combined to create an anaglyphic 3D image. The resulting stereo view, which can be seen at full size with a scale of about 100 meters/pixel by clicking on the image below, covers an area of 150 by 100 kilometers.