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Explore the structure of the Atmospheric Boundary Layer (ABL), turbulence, temperature measurements, and data reliability. Dive into turbulence modeling techniques and remote sensing for ABL analysis. Discover in-situ and remote sensing techniques for temperature profiling. Reflect on filtering methods and data inter-comparisons for enhanced accuracy in ABL studies.
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Atmospheric Boundary Layer (ABL) and Turbulence Tobias Wolf, Nansen Environmental and Remote Sensing Center Climate Change in the Arctic OceanNABOS 2013
NABOS 2013 Chapter 1 1. ABL structure, a quick overview2. Turbulence in the atmosphere and ocean3. Measuring Temperature Profiles in the ABL4. MTP-5HE
NABOS 2013 ABL as part of the troposphere Arya, S., Introduction to Micrometeorology, 2001 (1) ABL structure
NABOS 2013 ABL structure over land surfaces in mid-latitudes Stull, R.B., An Introduction to Boundary Layer Meteorology, 1997 (1) ABL structure
NABOS 2013 Surface energy balance over land Oke, T.R., Boundary Layer Climates, 1897 (1) ABL structure
NABOS 2013 Surface energy balance over water Oke, T.R., Boundary Layer Climates, 1897 (1) ABL structure
NABOS 2013 Surface energy balance over snow Oke, T.R., Boundary Layer Climates, 1897 (1) ABL structure
NABOS 2013 Chapter 2 1. ABL structure, a quick overview2. Turbulence in the atmosphere and ocean3. Measuring Temperature Profiles in the ABL4. MTP-5HE
Dissipation Lets assume Marie did not stir a cup but a supercup without friction at the glass. What would be the processes stopping my little tea-twister and how long would that take (the cup is 10 cm in diameter)? How to make Marie stir my tea (2) Turbulence
Kolmogorov theory on turbulent energy cascading Lewis Fry Richardson: Big whirls have little whirls, that feed on their velocity. And little whirls have lesser whirls, and so on to viscosity. Left: Vallis, G.K., Atmospheric and Oceanic Fluid Dynamics, 2006 Right: Grant et al., 1962 (2) Turbulence
Modelling techniques • Reynolds averaged numerical simulation (RANS) • Large Eddy Simulation (LES) • Direct Numerical Simulation (DNS) (2) Turbulence
NABOS 2013 Chapter 3 1. ABL structure, a quick overview2. Turbulence in the atmosphere and ocean3. Measuring Temperature Profiles in the ABL4. MTP-5HE
NABOS 2013 In-situ techniques • Meteorological towers • Radiosoundings • Teathered Balloons • RPAS • Measurement stations along the slope of mountains (3) Measuring temperature
NABOS 2013 Remote Sensing Techniques • Sound Detection and Ranging-Radar Acoustic Sounding System (SODAR-RASS) • Microwave Temperature Profiler (MTP) (3) Measuring temperature
Chapter 4 1. ABL structure, a quick overview2. Turbulence in the atmosphere and ocean3. Measuring Temperature Profiles in the ABL4. MTP-5HE
NABOS 2013 Atttex MTP-5HE 56.7 GHz thermal radiation at side slope of Oxygen absorption band Vertically resolved signal from angular scanning Vertical resolution: 25 m until 100 m and 50 m until 1000 m Temporal resolution: 5 min (3) MTP-5HE
NABOS 2013 Data Reliability Inter-comparison of filtered temperatures at the AMS and MTP-5HE at the heights of the AMS for |v| > 5 m/s (3) MTP-5HE
NABOS 2013 Filtering I Inter-comparison of all temperatures at the AMS and MTP-5HE at the heights of the AMS for |v| > 5 m/s Esau, Wolf et al., 2013, in print (3) MTP-5HE
NABOS 2013 Filtering II Top panel: MTP-5HE measurement during precipitation. Lower panel: rain rate measured with rain radar Esau, Wolf et al., 2013, in print (3) MTP-5HE
NABOS 2013 Filtering • What did we use in Bergen? RH from AMS at elevated location and nearby instrument. Rain radar • What could you use here? Ceilometer (LIDAR) Radiosoundings Cloud observations (3) MTP-5HE
NABOS 2013 Thank you for your attention