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Posted at 11:38 AM ET, 09/12/2012

NASA drone spies on tropical storm Nadine

Overnight, tropical depression 14 (TD14) gained enough intensity to earn the name Nadine, the 14th tropical storm of the 2012 Atlantic hurricane season. Our tropical weather expert, Brian McNoldy says he could only find two others years in 160 years of records in which the 14th storm formed sooner: 1936 and 2011.

Nadine is on a projected path that threatens no land area according to the National Hurricane Center, but a NASA field campaign is taking full advantage of this storm to get deeper insight into how hurricanes develop and intensify.


Flight path of NASA unmanned aircraft and its position over then tropical depression 14 (now Nadine) as of 5:30 p.m. EDT Tuesday. Its altitude at the time was 60,300 feet. (NASA)

Related: From tropical disturbance to hurricane: To be or not to be?

On Tuesday, NASA sent an unmanned Global Hawk into TD14/Nadine on a 26 hour mission to sample the storm’s environment. It is the longest continuous period a storm has ever been investigated, considerably longer than the capabilities of manned Air Force Hurricane Hunter planes. Climate Central’s Andrew Freedman put it this way: “To put that [26 hour flight] in further perspective, the longest regularly scheduled passenger flight is between Singapore and Newark, N.J., which clocks in at a comparatively paltry 18 hours and 55 minutes.”


One of two Global Hawks NASA is using to investigate tropical weather systems (NASA)
The drone that gazed down on Nadine is one of two Global Hawks NASA will dispatch from Wallops Island, Va. to collect data on tropical systems through early October and again in 2013 and 2014.

The planes are operated from ground control stations at Wallops and Dryden Flight Research Center at Edwards Air Force Base, Calif. The mission is formally known as the Hurricane and Severe Storm Sentinel (HS3).

NASA video overview of HS3

Reaching altitudes as high as 60,000 feet, the Hawks can fly above the highest-penetrating storms, while its suite of cutting-edge instruments can sense the air all the way down to the ocean surface.

Link: An interactive view of the Hawk aircraft

The two Hawks contain several sensors to take measurements - one focusing on the storm environment, the other - the “over storm Hawk” - which hones in on storm attributes like wind and rain rates.

The Environmental Global Hawk

“The primary objective of the environmental Global Hawk is to describe the interaction of tropical disturbances and cyclones with the hot, dry and dusty air that moves westward off the Saharan desert and appears to affect the ability of storms to form and intensify,” said Scott Braun, a NASA research meteorologist.

The suite of instruments includes:

* A Cloud Physics Lidar (CPL), which measures clouds structure and aerosols (dust, sea salt and smoke particles)

* A scanning high-resolution interferometer sounder (S-HIS), which can sense temperatures and water vapor from the surface through the atmosphere

* The Advanced Vertical Atmospheric Profiling System (AVAPS), which ejects small sensors tied to parachutes (cool!) to measure winds, temperature and humidity

The Over Storm Hawk

“Instruments on the ‘over-storm’ Global Hawk will examine the role of deep thunderstorm systems in hurricane intensity change, particularly to detect changes in low-level wind fields in the vicinity of these thunderstorms,” said Braun.

The suite of instruments includes:

* The High Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP), which measures cloud structure and winds in three dimensions

* The High-Altitude MMIC Sounding Radiometer (HAMSR), which uses microwave wavelengths to measure temperature, water vapor, and precipitation from the top of the storm to the surface

* A Hurricane Imaging Radiometer (HIRAD) which measures surface winds and rain rates

It’s too soon to evaluate how much valuable information this mission is collecting compared to manned aircraft such as Hurricane Hunters. But Climate Central’s Freedman says if the mission proves successful, the Hawks “might one day replace some of those conventional planes as a mainstay of hurricane recon work.”

By  |  11:38 AM ET, 09/12/2012

Categories:  Latest, Tropical Weather

 
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