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Volcanic eruptions are well known to affect aviation and climate. From ash particles spew into the atmosphere, they pose serious hazards for aviation safety due to the abrasive effects of volcanic ash to aircraft engines. However, ash particles are considered to have a short lifetime and are assumed to be removed quickly from the atmosphere. But gas-phase compounds such as H2O, CO2 and SO2 can remain longer. The latest, SO2, is converted into H2SO4 through oxidation with OH and rapidly transformed into sulfuric acid droplets, a mixture between sulfuric acid and water.

These tiny sulfate droplets have a lifetime of several years and produce a wide spread layer which can block part of solar radiation and reduce surface temperature on earth, also known as the umbrella effect.

The latest major eruption on earth was in 1991, from Mt Pinatubo. Since then, smaller but more frequent eruptions have affected the aerosol content of the stratosphere. One of them occurred in Indonesia in February, 13th 2014, the Kelud eruption.

As a part of the A-train, the CALIOP space-borne lidar made remarkable observations of the Kelud plume as shown by the curtain of backscatter coefficient (Figure 1). The plume top is seen up to 25 km, a remarkable level for such an event and the highest altitude reached by a volcanic eruption since more than two decades. The event caused a champagne-like eruption of explosive magnitude. Scientists will soon realize that this was not the only unique characteristic of the volcano.

Figure 1. (Top right corner) Brightness temperature (11 microns) from MODIS/Aqua together with the CALIOP/CALIPSO total attenuated backscatter lidar profiles along the orbit track. CALIPSO shows that the plume reached up to 26 km with a main cloud near 18-19 kmFigure 1. (Top right corner) Brightness temperature (11 microns) from MODIS/Aqua together with the CALIOP/CALIPSO total attenuated backscatter lidar profiles along the orbit track. CALIPSO shows that the plume reached up to 26 km with a main cloud near 18-19 km

As a part of the A-train, the CALIOP space-borne lidar made remarkable observations of the Kelud plume as shown by the curtain of backscatter coefficient (Figure 1). The plume top is seen up to 25 km, a remarkable level for such an event and the highest altitude reached by a volcanic eruption since more than two decades. This event was exceptional by his explosively, a champagne-like eruption, and scientists will quickly realize that was the only particularity of this volcano.

During the eruption, the ATTREX aircraft mission was going on in Guam, a small island in the middle of the Western Pacific. Soon after the eruption, stratospheric winds blew the volcanic plume toward an area where the Global Hawk, an unmanned UAV converted for atmospheric research, was used to study high altitude cirrus clouds. While this mission could have represented a unique opportunity to study this plume, it never happened.

Thus, a team of scientists from NASA Langley and the University of Wyoming decided to mount a field mission dedicated to study this plume. After a few weeks, observations from the CALIPSO lidar revealed unusual properties of the plume. Through depolarization measurements, sensitive to the geometrical properties of aerosol, scientists rapidly deduced that this plume was not only made of sulfuric acid droplets, the liquid and spherical particles expected to be produced from SO2 a few weeks after an eruption. Indeed, aspherical particles, crusty materials, and probably ash, was still largely present in the plume.

At this time, it became clear that additional measurements were needed to verify and validate observations from the CALIPSO lidar but also obtain ampler information of the physical and optical properties of these volcanic aerosols that satellite alone could not give. Within a few weeks, a proposal was submitted to NASA HQ and funding became available to launch small and large research balloons to study the Kelud plume, the KLASH (KeLud-ASH) campaign.

The KLASH campaign took place between 14-21th May 2014. Scientists deployed small and large aerosol payloads from the Northern Australian Territory North to intercept the Kelud plume and retrieve information on the physical and optical properties of volcanic aerosols which already circumnavigated the world several times in the tropical belt. The campaign consisted of the launch of 5 small COBALD backscatter sondes under weather balloons from Bureau of Meteorology in Darwin. In addition, a balloon flight combining Optical Particle Counters (OPCs) from the University of Wyoming took place from Corroboree, South of Darwin (Figure 3).

For flight guidance, a plume forecasting system was put together based upon the assimilation of CALIPSO observations of the plume into a Lagragian transport model. The movie below shows the evolution of the Kelud plume for a few days over the tropical belt and over Australia.

Figure 2. Movie representing the evolution of the Kelud plume across the tropical belt between 7-21th May 2014.Figure 2. Movie representing the evolution of the Kelud plume across the tropical belt between 7-21th May 2014.

The plume is seen to remain in the tropical stratosphere between 18-21 km with regular excursion over North Australia and the Darwin region spotted with the red square just before the campaign.

During the KLASH campaign, all balloon flights did see the Kelud plume in the lower stratosphere.Figure 3 shows extinction profiles derived from the COBALD backscatter sonde and OPC flights togetherwith an average profile from CALIPSO. All profiles show the Kelud plume between 18-22 km with some differences in extinction values.

Figure 3-1: Picture taken during the preparation of the OPC/COBALD flights from Corroboree on May, 20th. Figure 3-2: Extinction profiles from CALIOP/CALIPSO, OPC and COBALD during the KLASH campaign.
Figure 3. Picture taken during the preparation of the OPC/COBALD flights from Corroboree on May, 20th. (Right) Extinction profiles from CALIOP/CALIPSO, OPC and COBALD during the KLASH campaign.

Overall, data gathered during the KLASH campaign have been used to validate CALIPSO observations of volcanic ash, derive the size distribution of volcanic ash and sulfate in the plume and constrain radiative calculations.

We showed that 20-28 % of the radiative forcing of this volcanic plume more than 3 months after the eruption was exerted by volcanic ash and not entirely induced by volcanic sulfate aerosol. This results represents significant changes in our understanding of the lifetime of volcanic ash in the atmosphere and its longer than expected impact on our climate system.

Jean-Paul Vernier

  • Virginia DEQ, NASA and Penn State-NATIVE Enclosures (from right to left)
    Virginia DEQ, NASA and Penn State-NATIVE Enclosures (from right to left)

  • Ozone-sonde away.
    Ozone-sonde away.
  • About to lift.
    About to lift.
PurpleAir PA-II-SD Air Quality Sensor
Laser Particle Counters
Type (2) PMS5003
Range of measurement 0.3, 0.5, 1.0, 2.5, 5.0, & 10 μm
Counting efficiency 50% at 0.3μm & 98% at ≥0.5μm
Effective range
(PM2.5 standard)*
0 to 500 μg/m³
Maximum range (PM2.5 standard)* ≥1000 μg/m³
Maximum consistency error (PM2.5 standard) ±10% at 100 to 500μg/m³ & ±10μg/m³ at 0 to 100μg/m³
Standard Volume 0.1 Litre
Single response time ≤1 second
Total response time ≤10 seconds
Pressure, Temperature, & Humidity Sensor
Type BME280
Temperature range -40°F to 185°F (-40°C to 85°C)
Pressure range 300 to 1100 hPa
Humidity Response time (τ63%): 1 s
Accuracy tolerance: ±3% RH
Hysteresis: ≤2% RH


Pandora capabilities

Instrument

Response

Parameter

Precision

Uncertainty

Range

Resolution

Pandora

~2min

Total Column O3, NO2, HCHO, SO2, H2O, BrO

0.01 DU

0.1 DU

 

 

Virginia Department of Environment Quality in-situ instrumentation

Instrument

Response

Parameter

Precision

Uncertainty

Thermo Scientific 42C (Molybdenum converter)
(VADEQ)

60 s

NO and NOx

50 pptv

3%

Teledyne API 200EU w/ photolytic converter
(EPA) PI-Szykman

20 s

NO2

50 pptv

 

Thermo Scientific 49C (VADEQ)

20 s

O3

1 ppbv

4%

Thermo Scientific 48i (VADEQ)

60 s

CO

40 ppbv

5%

Thermo Scientific 43i (VADEQ)

80 s

SO2

0.2 ppbv

5%

Thermo Scientific 1400AB TEOM (VADEQ)

600 s

PM2.5 (continuous)

µg/m3

1 3%

Thermo Scientific Partisol Plus 2025 (VADEQ)

24 hr

PM2.5 (filter-based FRM)- 1/3 days

 

 

BSRN-LRC-49
Large area view.
Latitude: 37.1038
Longitude: -76.3872
Elevation: 3 m Above sea level
Scenes: urban, marsh, bay, river and farm.

Legend

  • The inner red circle is a 20km CERES foot print centered on the BSRN-LRC site.
  • The pink circle represents a possible tangential 20km foot print.
  • The middle red circle represents the area in which a 20km foot print could fall and still see the site.
  • Yellow is a sample 40 deg off nadir foot print.
  • The outer red circle is the region which would be seen by a possible 40 deg off nadir foot print.
The BSRN-LRC sun tracker at the NASA Langley Research Center on a snowy day (02/20/2015) The BSRN-LRC sun tracker at the NASA Langley Research Center on a snowy day (02/20/2015)
CAPABLE-BSRN Google Site Location Image

Team Satellite Sensor G/L Dates Number of obs Phase angle range (°)
CMA FY-3C MERSI LEO 2013-2014 9 [43 57]
CMA FY-2D VISSR GEO 2007-2014
CMA FY-2E VISSR GEO 2010-2014
CMA FY-2F VISSR GEO 2012-2014
JMA MTSAT-2 IMAGER GEO 2010-2013 62 [-138,147]
JMA GMS5 VISSR GEO 1995-2003 50 [-94,96]
JMA Himawari-8 AHI GEO 2014- -
EUMETSAT MSG1 SEVIRI GEO 2003-2014 380/43 [-150,152]
EUMETSAT MSG2 SEVIRI GEO 2006-2014 312/54 [-147,150]
EUMETSAT MSG3 SEVIRI GEO 2013-2014 45/7 [-144,143]
EUMETSAT MET7 MVIRI GEO 1998-2014 128 [-147,144]
CNES Pleiades-1A PHR LEO 2012 10 [+/-40]
CNES Pleiades-1B PHR LEO 2013-2014 10 [+/-40]
NASA-MODIS Terra MODIS LEO 2000-2014 136 [54,56]
NASA-MODIS Aqua MODIS LEO 2002-2014 117 [-54,-56]
NASA-VIIRS NPP VIIRS LEO 2012-2014 20 [50,52]
NASA-OBPG SeaStar SeaWiFS LEO 1997-2010 204 (<10, [27-66])
NASA/USGS Landsat-8 OLI LEO 2013-2014 3 [-7]
NASA OCO-2 OCO LEO 2014
NOAA-STAR NPP VIIRS LEO 2011-2014 19 [-52,-50]
NOAA GOES-10 IMAGER GEO 1998-2006 33 [-66, 81]
NOAA GOES-11 IMAGER GEO 2006-2007 10 [-62, 57]
NOAA GOES-12 IMAGER GEO 2003-2010 49 [-83, 66]
NOAA GOES-13 IMAGER GEO 2006 11
NOAA GOES-15 IMAGER GEO 2012-2013 28 [-52, 69]
VITO Proba-V VGT-P LEO 2013-2014 25 [-7]
KMA COMS MI GEO 2010-2014 60
AIST Terra ASTER LEO 1999-2014 1 -27.7
ISRO OceanSat2 OCM-2 LEO 2009-2014 2
ISRO INSAT-3D IMAGER GEO 2013-2014 2

The NASA Prediction Of Worldwide Energy Resources (POWER) Project improves the accessibility and usage NASA Earth Observations (EO) supporting community research in three focus areas: 1) renewable energy development, 2) building energy efficiency, and 3) agroclimatology applications. The latest POWER version enhances its distribution systems to provide the latest NASA EO source data, be more resilient, support users more effectively, and provide data more efficiently. The update will include hourly-based source Analysis Ready Data (ARD), in addition to enhanced daily, monthly, annual, and climatology ARD. The daily time-series now spans 40 years for meteorology available from 1981 and solar-based parameters start in 1984. The hourly source data are from Clouds and the Earth's Radiant Energy System (CERES) and Global Modeling and Assimilation Office (GMAO), spanning 20 years from 2001.

The newly available hourly data will provide users the ARD needed to model the energy performance of building systems, providing information directly amenable to decision support tools introducing the industry standard EPW (EnergyPlus Weather file). One of POWER’s partners, Natural Resource Canada’s RETScreen™, will be simultaneously releasing a new version of its software, which will have integrated POWER hourly and daily ARD products. For our agroclimatology users, the ICASA (International Consortium for Agricultural Systems Applications standards) format for the crop modelers has been modernized.

POWER is releasing new user-defined analytic capabilities, including custom climatologies and climatological-based reports for parameter anomalies, ASHRAE® compatible climate design condition statistics, and building climate zones. The ARD and climate analytics will be readily accessible through POWER's integrated services suite, including the Data Access Viewer (DAV). The DAV has been improved to incorporate updated parameter groupings, new analytical capabilities, and the new data formats. Updated methodology documentation and usage tutorials, as well as application developer specific pages, allow users to access to POWER Data efficiently.

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