Identification

Title

Relationship of snow microphysics and precipitation generation to vertical motions in extratropical cyclones: Results from IMPACTS

Abstract

This study analyzes in situ aircraft microphysical measurements in deep snow-producing clouds during the Investigation of Microphysics and Precipitation for Atlantic Coast-Threatening Snowstorms (IMPACTS) field programs in winter 2020, 2022, and 2023 to characterize and compare the microphysics in the updraft and downdraft regions. Measurements were acquired from the NASA P-3 aircraft equipped with a full complement of particle probes and instruments for direct measurements of condensed water content and thermodynamic and 3D wind measurements. We identified the P-3 aircraft flight days collected within snowbands, generating cells, and peripheral regions from 14 flights. These are composited and used for the analysis. Temperatures sampled ranged between −27° and +1°C. The data are partitioned by air vertical velocity, with strong updrafts defined as >0.5 m s −1 , very strong updrafts as >1 m s −1 , and strong downdrafts as <−0.5 m s −1 . This partitioning revealed precipitation mass concentrations that were 2x higher in the strong updrafts and 3x higher in the very strong updrafts than in the downdrafts, a result of particle growth and relative fallout within the updrafts. Total particle concentrations at the concentrations > 1 mm were about the same in each region. However, fallout of the larger aggregates through the updrafts at temperatures > −5°C and into the melting layer results in previously unreported shedding and lofting of the shed particles in the updrafts to subfreezing temperatures. This observation is supported by the overflying NASA ER-2 Doppler radar measurements.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.net/ark:/85065/d7tf02s6

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

2025-06-01T00:00:00Z

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