Sökning: id:"swepub:oai:DiVA.org:ltu-6340" >
Turbulence associat...
Turbulence associated with mountain waves over Northern Scandinavia : a case study using the ESRAD VHF radar and the WRF mesoscale model
-
- Kirkwood, Sheila (författare)
- Swedish Institute of Space Physics / Institutet för rymdfysik
-
- Mihalikova, Maria (författare)
- Swedish Institute of Space Physics / Institutet för rymdfysik
-
- Rao, T.N. (författare)
- National Atmospheric Research Laboratory, Gadanki
-
visa fler...
-
- Satheesan, K. (författare)
- Swedish Institute of Space Physics / Institutet för rymdfysik
-
visa färre...
-
(creator_code:org_t)
- 2010-04-16
- 2010
- Engelska.
-
Ingår i: Atmospheric Chemistry And Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 10, s. 3583-3599
- Relaterad länk:
-
https://www.atmos-ch...
-
visa fler...
-
https://urn.kb.se/re...
-
https://doi.org/10.5...
-
visa färre...
Abstract
Ämnesord
Stäng
- We use measurements by the 52 MHz wind-profiling radar ESRAD, situated near Kiruna in Arctic Sweden, and simulations using the Advanced Research and Weather Forecasting model, WRF, to study vertical winds and turbulence in the troposphere in mountain-wave conditions on 23, 24 and 25 January 2003. We find that WRF can accurately match the vertical wind signatures at the radar site when the spatial resolution for the simulations is 1 km. The horizontal and vertical wavelengths of the dominating mountain-waves are ~10–20 km and the amplitudes in vertical wind 1–2 m/s. Turbulence below 5500 m height, is seen by ESRAD about 40% of the time. This is a much higher rate than WRF predictions for conditions of Richardson number (Ri) <1 but similar to WRF predictions of Ri<2. WRF predicts that air crossing the 100 km wide model domain centred on ESRAD has a ~10% chance of encountering convective instabilities (Ri<0) somewhere along the path. The cause of low Ri is a combination of wind-shear at synoptic upper-level fronts and perturbations in static stability due to the mountain-waves. Comparison with radiosondes suggests that WRF underestimates wind-shear and the occurrence of thin layers with very low static stability, so that vertical mixing by turbulence associated with mountain waves may be significantly more than suggested by the model
Ämnesord
- TEKNIK OCH TEKNOLOGIER -- Maskinteknik -- Rymd- och flygteknik (hsv//swe)
- ENGINEERING AND TECHNOLOGY -- Mechanical Engineering -- Aerospace Engineering (hsv//eng)
Nyckelord
- Space Technology
- Rymdteknik
Publikations- och innehållstyp
- ref (ämneskategori)
- art (ämneskategori)
Hitta via bibliotek
Till lärosätets databas