|
Titel |
Lifted temperature minimum during the atmospheric evening transition |
VerfasserIn |
E. Blay-Carreras, E. R. Pardyjak, D. Pino, S. W. Hoch, J. Cuxart, D. Martínez, J. Reuder |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1680-7316
|
Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Chemistry and Physics ; 15, no. 12 ; Nr. 15, no. 12 (2015-06-29), S.6981-6991 |
Datensatznummer |
250119854
|
Publikation (Nr.) |
copernicus.org/acp-15-6981-2015.pdf |
|
|
|
Zusammenfassung |
Observations of lifted temperature minimum (LTM) profiles in the nocturnal
boundary layer were first reported in 1932. It was defined by the existence
of a temperature minimum some centimetres above the ground. During the
following decades, several research studies analysed this phenomenon
verifying its existence and postulating different hypotheses about its
origin.
The aim of this work is to study the existence and characteristics of LTM
during the evening transition by using observations obtained during the
Boundary Layer Late Afternoon and Sunset Turbulence (BLLAST) campaign. Data
obtained from two masts instrumented with thermocouples and wind sensors at
different heights close to the ground and a mast with radiometers are used
to study the role of mechanical turbulence and radiation in LTM development.
The study shows that LTM can be detected under calm conditions
during the day–night transition, several hours earlier than reported in
previous work. These conditions are fulfilled under weak synoptic forcing
when the local flow shifts associated with a mountain–plain circulation in
relatively complex orography. Under these special conditions, turbulence
becomes a crucial parameter in determining the ideal conditions for observing
LTM. Additionally, LTM observed profiles are also related to
a change in the atmospheric radiative characteristics under calm conditions. |
|
|
Teil von |
|
|
|
|
|
|