Identification

Title

Atmospheric mercury over the NE Pacific during spring 2002: Gradients, residence time, upper troposphere lower stratosphere loss, and long-range transport

Abstract

Gaseous elemental mercury (GEM) was measured over the North Pacific and coastal California, Oregon and Washington in spring 2002 during the Intercontinental Transport and Chemical Transformation Experiment-2002 (ITCT2K2). Observations were made from the NOAA WP3 on 11 flights which spanned an altitude range of 0-8 km and latitudes between 35 and 55°N. GEM was determined using a Tekran 2537A mercury instrument modified for airborne use to collect and analyze samples every 2.5 min under variable ambient temperature and pressure conditions. GEM concentrations were in general at the low end of previous measurements made over continents and in fresh continental outflow over the ocean. They showed (1) a significant vertical gradient in GEM between the lower sample altitudes and the upper altitudes, with median concentrations decreasing from 1.2 to 0.5 ng m⁻³; (2) GEM was depleted in upper troposphere lower stratospheric air and indicated this region is a sink for GEM; (3) GEM concentrations were ∼1/2 at the surface to ∼1/4 at midaltitudes of those observed immediately downwind of Asia during ACE-Asia, however; (4) highest GEM concentrations (∼4 ng m⁻³) were found in plume layers at concentrations comparable to those observed off the Asian coast in ACE-Asia; and (5) the observed variance in GEM suggested a lifetime on the order of 100 days, which was shorter than the previously accepted nominal lifetime of 1 year.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7z89cn2

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2007-10-11T00:00:00Z

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

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact