Identification

Title

New 3-D simulations of climate change in the thermosphere

Abstract

Model simulations of temperature and density trends in the upper thermosphere are generally consistent with satellite drag data, but some discrepancies remain. The most important of these is that satellite drag analyses under solar minimum conditions have measured density change of about -5% per decade near 400 km altitude, while model simulations of upper atmosphere cooling due to anthropogenic increases in carbon dioxide and other trace gases have predicted about half that rate. For solar moderate and maximum conditions, agreement is better. The rate of change is less during higher solar activity, because higher levels of nitric oxide cooling compete with the anthropogenic cooling. However, some past modeling studies used global mean models, and others attempted to scale to decadal rates from scenarios where carbon dioxide was doubled. Both of these approaches have shortcomings. Therefore, we have performed new, fully 3-D simulations, using the National Center for Atmospheric Research thermosphere-ionosphere-mesosphere electrodynamics general circulation model, to better quantify secular change rates at various levels of solar activity. These simulations use a 12 year baseline (approximately one solar cycle) in order to more directly compare with measured rates. Our new findings are in better agreement with observations for solar minimum conditions, approximately -5% per decade at 400 km, and are also still in reasonable agreement at solar maximum, approximately -2% per decade. This confluence of observation and simulation strengthens the case that some of the best evidence of the impact of anthropogenic global change on the upper atmosphere is the continued systematic decrease of thermospheric density.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7hm59n4

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

2015-03-01T00:00:00Z

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