NOUS41 KWBC 031330

PNSWSH

 

Technical Implementation Notice 16-06

National Weather Service Headquarters Washington DC

930 AM EST Thu Mar 3 2016

 

To:        Subscribers:

           -Family of Services

           -NOAA Weather Wire Service

           -Emergency Managers Weather Information Network

           -NOAAPORT

           Other NWS Partners, Users and Employees

 

From:      Tim McClung

           Chief Operating Officer

           NWS Office of Science and Technology Integration                                  

 

Subject:   New NGAC Aerosol Forecast System

           Effective April 5, 2016

 

Effective on or about April 5, 2016, starting with the 

1200 Coordinated Universal Time (UTC) cycle, the National

Centers for Environmental Prediction (NCEP) will begin to

run and disseminate data from the NOAA Environment Modeling

System (NEMS) Global Forecast System (GFS) Aerosol

Component Version 2 system (NGACv2).

 

NGAC is a global in-line atmospheric-aerosol module within

the NEMS GFS. The aerosol component of the NGAC is the

Goddard Chemistry Aerosol Radiation and Transport Model

(GOCART).

 

The scope of this upgrade includes:

- Extending aerosol species from dust only to multiple

species including dust, sea salt, sulfate, organic carbon

and black carbon aerosols to provide more complete global

aerosol forecast using near real time global biomass

burning emission data GBBEPx

- Updating meteorological model physics including RRTM with

McICA radiation package, Eddy-Diffusivity Mass-Flux (EDMF)

PBL scheme and land surface updates on canopy height

scheme, soil moisture nudge and roughness length

- Fixing bugs such as AOD computation and error message in

MPI quit.

 

Emission sources/techniques used for new species are:

 - source for sulfate: daily biomass burning emissions from

NESDIS GBBEPx, and biofuel and fossil fuel emissions from

AeroCom anthropogenic emissions. DMS source is a

climatology of oceanic DMS concentrations (Chin et al. J.

Atmos. Sci., 2002).

- sources for carbonaceous aerosols: daily biomass burning

emissions from NESDIS GBBEPx, biofuel and fossil fuel

climatology from AeroCom anthropogenic emissions, and

climatology EDGAR based ship emissions. Organic carbon also

has Terpene emission.

- emission techniques for sea salt: NGACv2 has 5 size sea

salt bins (dry radius range: 0.03-10micron), the emission

is a function of particle size and surface wind speed (Gong

S., Global Biogeochem. Cy. 2003)

- Model will now be run twice daily: 00Z and a new 12Z

cycle

- Standardization of file names

- New fields in all output files (listed below)

 

The expected benefits/impacts include providing:

- Guidance on long range aerosol transport and the impact

on Particulate Matter (PM) pollution impacting the U.S.

- Dynamic aerosol lateral boundary conditions to regional

air quality model

- Multi-species aerosol forecasts to end users for

applications such as SST retrieval and UV index forecast.

 

The changes to the files names are as follows:

 

Where: HHH=00 to 120 in 3hr increments and CC=00, 12(new)

 

            Old                         New

ngac.tCCz.a2dfHHH    ->  ngac.tCCz.a2dfHHH.grib2

ngac.tCCz.a3dfHHH    ->  ngac.tCCz.a3dfHHH.grib2

ngac.tCCz.aod_340nm  ->  ngac.tCCz.aod_340nm.grib2

ngac.tCCz.aod_440nm  ->  ngac.tCCz.aod_440nm.grib2

ngac.tCCz.aod_550nm  ->  ngac.tCCz.aod_550nm.grib2

ngac.tCCz.aod_660nm  ->  ngac.tCCz.aod_660nm.grib2

ngac.tCCz.aod_1p63um ->  ngac.tCCz.aod_1p63um.grib2

ngac.tCCz.aod_11p1um ->  ngac.tCCz.aod_11p1um.grib2

 

 

The output files will now include these new fields:

 

(1) ngac.tCCz.a2dfHHH.grib2, where HHH=00,03,...,120 &

CC=00,12:

 

New fields:

 

ASYSFK: Asymmetry Factor at 340 nm from total aerosols

[Numeric]

SSALBK: Single Scattering Albedo at 340 nm from total

aerosols [Numeric]

AOTK: Aerosol Optical Thickness at 550 nm from total

aerosols [Numeric]

AOTK: Aerosol Optical Thickness at 550 nm from sea salt

aerosol [Numeric]

AOTK: Aerosol Optical Thickness at 550 nm from black carbon

dry aerosol [Numeric]

AOTK: Aerosol Optical Thickness at 550 nm from particulate

organic carbon dry aerosol [Numeric]

AOTK: Aerosol Optical Thickness at 550 nm from sulphate dry

aerosol [Numeric]

DUST_SCAVENGING_FLUX: dust wet Deposition by Convective

Precipitation Flux fluxes (kg/m2/sec)

SEASALT_EMISSION_FLUX: sea salt emission mass flux

(kg/m2/sec)

SEASALT_SEDIMENTATION_FLUX: sea salt sedimentation mass

flux (kg/m2/sec)

SEASALT_DRY_DEPOSITION_FLUX: sea salt dry deposition mass

flux (kg/m2/sec)

SEASALT_WET_DEPOSITION_FLUX: sea salt wet deposition by

large scale precipitation mass flux (kg/m2/sec)

SEASALT_SCAVENGING_FLUX: sea salt wet deposition by

convective precipitation mass flux (kg/m2/sec)

BC_EMISSION_FLUX: black carbon emission mass flux

(kg/m2/sec)

BC_SEDIMENTATION_FLUX: black carbon sedimentation mass flux

(kg/m2/sec)

BC_DRY_DEPOSITION_FLUX: black carbon dry deposition mass

flux (kg/m2/sec)

BC_WET_DEPOSITION_FLUX: black carbon wet deposition by

large scale precipitation mass flux (kg/m2/sec)

BC_SCAVENGING_FLUX: black carbon wet deposition by

convective precipitation mass flux (kg/m2/sec)

OC_EMISSION_FLUX: particulate organic carbon emission mass

flux (kg/m2/sec)

OC_SEDIMENTATION_FLUX: particulate organic carbon

sedimentation mass flux (kg/m2/sec)

OC_DRY_DEPOSITION_FLUX: particulate organic carbon dry

deposition mass flux (kg/m2/sec)

OC_WET_DEPOSITION_FLUX: particulate organic carbon wet

deposition by large scale precipitation mass flux

(kg/m2/sec)

OC_SCAVENGING_FLUX: particulate organic carbon wet

deposition by convective precipitation mass flux

(kg/m2/sec)

 

(2) ngac.tCCz.a3dfHHH.grib2, where HHH=00,03,...,120 &

CC=00,12:

 

New fields:

 

SEASALT1: sea salt bin1 (diameter: 0.06-0.2 micron) mixing

ratio (kg/kg)

SEASALT2: sea salt bin2 (diameter: 0.2-1 micron) mixing

ratio (kg/kg)

SEASALT3: sea salt bin3 (diameter: 1-3 micron) mixing ratio

(kg/kg)

SEASALT4: sea salt bin4 (diameter: 3-10 micron) mixing

ratio (kg/kg)

SEASALT5: sea salt bin5 (diameter: 10-20 micron) mixing

ratio (kg/kg)

BC1: black carbon hydrophobic dry (median diameter: 0.0236

micron), mixing ratio (kg/kg)

BC2: black carbon hydrophilic dry (median diameter: 0.0236

micron), mixing ratio (kg/kg)

OC1: particulate organic carbon hydrophobic dry (median

diameter: 0.0424 micron), mixing ratio (kg/kg)

OC2: particulate organic carbon hydrophilic dry (median

diameter: 0.0424 micron), mixing ratio (kg/kg)

SO4: sulphate dry (median diameter: 0.139 micron), mixing

ratio (kg/kg)

 

 

(3) ngac.tCCz.aod_$NM.grib2, where NM=11p1um, 1p63um,

340nm, 440nm, 550nm, 660nm, 860nm & CC=00,12:

Total aerosol optical depth at specified wavelengths (11.1,

1.63, 0.34, 0.44, 0.55, 0.66, and 0.86 micron)

 

Note: NGACv1 total aerosol optical depth is from dust only.

NGACv2 total aerosol optical depth is from multiple species

including dust, sea salt, sulphate, black carbon and

particulate organic carbon

 

New fields:

ngac.t00z.aod_550nm.grib2 file also contains aerosol

optical depth at 550nm from each species: dust, sea salt,

sulfate, organic carbon and black carbon.

 

 

The NGAC output will continue to be disseminated via NCEP's

ftp/http server at the following locations:

 

http://www.nomads.ncep.noaa.gov/pub/data/nccf/com/ngac/prod

http://www.ftp.ncep.noaa.gov/data/nccf/com/ngac/prod

ftp://ftp.ncep.noaa.gov/pub/data/nccf/com/ngac/prod

 

Web graphics will remain available at:

 

http://www.emc.ncep.noaa.gov/gmb/NGAC/html/realtime.ngac.html

 

A consistent parallel feed of data will be available on the

NCEP server via the following URL:

 

http://para.nomads.ncep.noaa.gov

 

NGAC products are encoded in GRIB2. The NCEP grib2 table is

updated to include the definition of new aerosol types.

Users should download the latest versions of wgrib2 and the

other NCEP GRIB utilities to use the NGAC output products. 

 

A website containing retrospective run results from NGACv2

for the period of Apr2015-Feb2016 is at:

 

http://www.emc.ncep.noaa.gov/gmb/NGAC/V2/

 

For questions regarding the scientific content of the NGAC

model, please contact:

 

Jun Wang

NCEP/EMC

College Park, Maryland 20740

301-683-3811

jun.wang@noaa.gov

 

For questions regarding the dataflow aspects of these data

sets, please contact:

 

Carissa Klemmer

NCEP Dataflow Team Lead

College Park, Maryland 20740

301-683-0567

ncep.list.pmb-dataflow@noaa.gov

 

National Technical Implementation Notices are online at:

 

http://www.nws.noaa.gov/os/notif.htm

 

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