Identification

Title

NCAR ACD FLEXPART Backtrajectories (Ground Sites)

Alternative title(s)

373.008

Abstract

This dataset contains output of FLEXPART, a Lagrangian Particle Dispersion Model (LPDM) for the time period 1 June to 14 July 2013. It provides information on the history of air sampled at the ground sites by releasing "particles" (infinitesimally small parcels of air) from the field site location and following its path backwards in time. Advection, turbulence and convection are the processes considered. A particle itself is "inert", processes like deposition, emission or chemical conversion are not considered. Thereby the result could be called "airmass history", as the particles behave like air. Its location back in time and space since released is called "backtrajectory". The chaotic nature of the atmosphere and uncertainties in model estimates of wind vector, turbulence and convection requires a statistical approach to estimate all probable backtrajectories. Hence not only one, but a large number of particles (1e5 - 1e6) are released over a short time period (1 hr) and followed back in time. While the exact trajectory for each particle is used internally, the main model result is the number of particles and the time they spent within a 3D latitude / longitude / altitude grid, called a "sensitivity" or "residence time" field. This is calculated at discrete intervals (every hour) in time since release. These fields are the raw output of the model calculations. For ease of use, deterministic backtrajectories as mass weighted mean of the plume at each hour, and 5 plume cluster centroids (Stohl et al., Atm. Env., 2002) are calculated as well. The dataset consists of three types of data: png - overview plot, icartt - trajectories as text, nc - raw (and most accurate) model output. The data were collected from 5 sites: CTR - Centreville, AL, SEARCH site at -87.2499, 32.9039 AABC - Alabama Aquatic Biodiversity Center (tower) at -87.2490, 32.6942 Lookrock - Look rock, TN, at -83.9416, 35.6334 RTP - Research Triangle Park, NC, at -78.8791, 35.8880 BHM - Birmingham, AL, at -86.8147, 33.5530 Note that the NetCDF portion of this dataset was updated on 31 July 2014. Please make sure to properly acknowledge this dataset in publications or presentations, or consider offering co-authorship if you deem it to be a substantial contribution to your work.

Resource type

dataset

Resource locator

https://data.eol.ucar.edu//dataset/373.008

protocol: https

name: NCAR ACD FLEXPART Backtrajectories (Ground Sites) homepage

description: Dataset homepage

https://data.eol.ucar.edu/cgi-bin/codiac/fgr_form/id=373.008

protocol: https

name: NCAR ACD FLEXPART Backtrajectories (Ground Sites) Data Order Form

description: Dataset order request form. Data files are made available via FTP.

function: order

Unique resource identifier

code

373.008

codeSpace

Dataset language

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

climatologyMeteorologyAtmosphere

Keywords

Keyword set

keyword value

dataset

originating controlled vocabulary

title

Resource Type

reference date

date type

revision

effective date

2014-10-16

Keyword set

keyword value

FLEXible PARTicle dispersion model - FLEXPART

Keyword set

keyword value

Models/Analyses

Geographic location

West bounding longitude

-105.00000

East bounding longitude

-72.00000

North bounding latitude

45.00000

South bounding latitude

24.00000

Temporal reference

Temporal extent

Begin position

2013-06-01T00:00:00Z

End position

2013-07-14T23:59:59Z

Dataset reference date

date type

publication

effective date

2013-10-29T18:28:04Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

none

Limitations on public access

none

Responsible organisations

Responsible party

contact position

EOL Data Support

organisation name

UCAR/NCAR - Earth Observing Laboratory

full postal address

PO Box 3000

Boulder

80307-3000

email address

datahelp@eol.ucar.edu

web address

https://data.eol.ucar.edu/

name: homepage

responsible party role

pointOfContact

Responsible party

contact position

EOL Data Support

organisation name

UCAR/NCAR - Earth Observing Laboratory

full postal address

PO Box 3000

Boulder

80307-3000

email address

datahelp@eol.ucar.edu

web address

https://data.eol.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact

contact position

EOL Data Support

organisation name

UCAR/NCAR - Earth Observing Laboratory

full postal address

PO Box 3000

Boulder

80307-3000

email address

datahelp@eol.ucar.edu

web address

https://data.eol.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata date

2024-02-07T22:45:10Z

Metadata language

eng; USA