CLOUD PHYSICS LIDARfor GOES-R

Matthew McGill / Goddard Space Flight Center

April 8, 2015

CPL is a self-contained, autonomous backscatter lidar capable of sustained operation at 20 km.

In operation since 2000.

Over two dozen field campaigns, and many 100’s of flight hours.

Housed in ER-2 forward superpod.

The CPL Instrument

Saharan dust

boundary layer aerosol

subvisual cirrus cirrus

low-level cumulus convective clouds

Lidar profiling generates a time-height cross-section of the atmosphere,revealing cloud and aerosol structure.

Multiple cloud/layer features can be measured, up to the limit of signalattenuation (O.D. 3-4).

From this data we derive layer boundaries, optical depth, extinction, and depolarization, and at least a coarse discrimination of aerosol type (e.g., smoke, dust, pollution).

CPL Data Example

1. Summary images for each flight (gif images).

2. Layer boundaries for PBL, elevated aerosol layers, clouds (output available in text file).

3. Optical properties, including- layer optical depth

- layer extinction-to-backscatter ratio (S)- layer extinction profile- layer transmission profile- images for extinction and optical depth- depolarization ratio

All data products are 1 second averages produced from theraw 1/10 second data.

All data products are produced for each wavelength.

In addition, real-time data display using Iridium/Inmarsat permits real-time verification of target acquisition and/or adaptive targeting.

CPL Data Products

CPL provides high resolution profiling of cloud and aerosol structure, up to the limitof signal attenuation. Data is provided with 30 m vertical resolution and 1 secondtemporal resolution. Higher-level data products, such as optical depth, are also produced.

CPL Data Example

Combining lidar and radar reveals the whole profile

CPL 532 nm attenuated backscatter ratio: 28 July

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merged profile characterization (green = lidar only; red = radar only; yellow = both)

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18:16:59 18:33:00time (UTC)18:22:20 18:27:40

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merged CPL+CRS normalized signal

18:16:59 18:33:00time (UTC)18:22:20 18:27:400.0

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layer finding and typing

extinction profiles

optical depth(total, cloud only,

aerosol only)

Example of CPL Higher-level Data Products

CPL Data Archived to CPL Web Site

Data available by experiment

http://cpl.gsfc.nasa.gov