mo4.l10 - automated monitoring of volcanic ash micro- and macro-physical properties: a comparison of...

Automated Monitoring of Volcanic Ash Micro and Macro-Physical Properties: A comparison of Future and Current

Satellite Instrument Capabilities

Michael Pavolonis (NOAA/NESDIS/STAR)

Marco Fulle - www.stromboli.net

Topics

• Motivation

• Retrieving volcanic ash properties

• Comparing sensor capabilities

• Applications for decision support

• Summary


The Eyjafjallajökull Eruption:

•Nearly 100,000 canceled flights

•Airlines were losing $200 million/day

•Total economic impact - $2 billion

Before Ash Event During Ash Event

Why is Volcanic Ash Monitoring Important?

Topics

• Motivation




• Summary


Volcanic Ash Properties•Retrievable ash cloud properties: effective temperature, emissivity, and a microphysical parameter (mainly related to particle size)

•From these retrieved parameters, the effective ash cloud height, mass loading, and effective particle radius can be calculated.

•The retrieval is performed using optimal estimation (e.g. Heidinger and Pavolonis, 2009).

•Possible channel combinations:

1). 11/12 µm

2). 11/13.3 µm

3). 11/12/13.3 µm

XLEOVIIRS

XGEOSEVIRI

XGEOMTSAT

XLEOMODIS

XGEOFY2

XGEOGOES-R ABI

XGEOGOES-12 - GOES-15 Imagers

XGEOGOES-11 Imager

XLEOAVHRR

11/12/13.3 µm channel

combination

11/13.3 µm channel

combination

11/12 µm channel

combination

OrbitSensor

In order to provide global volcanic ash products at high temporal resolution, the following imaging sensors are needed.

Volcanic Ash Properties•Regardless of the channel combination, the same ash cloud properties (ash height, mass loading, and effective particle radius) are always produced.

Volcanic Ash Properties

•Quantitative ash detection (Pavolonis 2010) is expressed as an ash confidence.

•Ash detection results can be overlaid on false color imagery to give the user perspective.

•The ash detection can be used to provide automated ash alerts.

Quantitative Ash Detection


•Ash mass loading (ton/km2) is needed to determine if jet engine tolerances are exceeded and to initialize models.

•If a 1 km cloud thickness is assumed, the mass loading is numerically equivalent to ash concentration in mg/m3.

Ash Mass Loading


•The ash cloud top height is critically important for determining if ash is at jetliner cruising altitudes (nowcasting component).

•In addition, the ash cloud height is a very important parameter for initializing dispersion models (forecasting component).

Ash Cloud Height


•The ash cloud effective particle radius is not a required GOES-R product, but it is automatically generated as part of the ash retrieval.

•The effective particle radius is well correlated with ash residence time.

Ash Effective Radius

Topics

• Motivation




• Summary


Ash clouds

May 7, 2010 (14:00 UTC)

Ash clouds

May 7, 2010 (14:00 UTC)

•Single channel IR window

Ash clouds

May 7, 2010 (14:00 UTC)


•11/13.3 µm retrieval

Ash clouds

May 7, 2010 (14:00 UTC)



•11/12 µm retrieval

Ash clouds

May 7, 2010 (14:00 UTC)




•11/12/13.3 µm retrieval

Ash cloud

February 12, 2010 (05:30 UTC)


February 12, 2010 (05:30 UTC)

Ash cloud




•11/12/13.3 µm retrieval

February 12, 2010 (05:30 UTC)

Ash cloud

Ash Cloud Height Validation

11/12 µm

11/12/13.3 µm

11/13.3 µm

11/13.3 µm 11/12 µm

11/12/13.3 µmAsh Mass Loading Validation

Topics

• Motivation




• Summary


•The ash cloud property products can be used to issue automated ash cloud alerts to VAAC’s.

•Decision support systems like this are needed because it is impossible to manually analyze every satellite image in real-time. In addition, the high temporal resolution of future geostationary measurements (like from GOES-R) will not be fully utilized for volcanic cloud monitoring without an automated alert system.

Text Warning

Quantitative description of ash cloud

Product Quick-look

Ash trajectories initialized using GOES-R retrievals

Model trajectories courtesy of Brad Pierce (NOAA/NESDIS)

Topics

• Motivation




• Summary


Summary• In order to provide global information on ash cloud properties

in a timely manner, a flexible retrieval algorithm is needed to accommodate three different infrared channel combinations (11/12, 11/13.3, and 11/12/13.3 µm).

• Comparisons to spaceborne lidar indicate that the 11/12/13.3 µm channel combination, which was developed for GOES-R, is significantly more accurate than the 2-channel combinations, especially for optically thin high ash clouds.

• Using SEVIRI, the GOES-R products were provided to the London VAAC during the eruption of Eyjafjallajökull.

• The 2-channel combinations still offer valuable information on ash cloud properties, especially if bias corrected.

• Current efforts are focused on developing a global, multi-sensor automated ash alert system and model initialization and assimilation studies.

Eyjafjallajökull(05/08/2010, 15:00 UTC) - 11/13.3 µm Algorithm

Eyjafjallajökull(05/08/2010, 15:00 UTC) - 11/12 µm Algorithm

Eyjafjallajökull(05/08/2010, 15:00 UTC) - 11/12/13.3 µm Algorithm

11/13.3 µm 11/12 µm

11/12/13.3 µm

Soufriere Hills (02/12/2010, 04:00 UTC) - 11/13.3 µm Algorithm

Soufriere Hills (02/12/2010, 04:00 UTC) - 11/12 µm Algorithm

Soufriere Hills (02/12/2010, 04:00 UTC) - 11/12/13.3 µm Algorithm

11/13.3 µm 11/12 µm

11/12/13.3 µm

mo4.l10 - automated monitoring of volcanic ash micro- and macro-physical properties: a comparison of...

Documents