Climate Change in the Arctic Ocean NABOS 2013 Atmospheric Boundary Layer (ABL) and Turbulence Tobias Wolf, Nansen Environmental and Remote Sensing Center

2NABOS 2013 Chapter 1 1. ABL structure, a quick overview 2. Turbulence in the atmosphere and ocean 3. Measuring Temperature Profiles in the ABL 4. MTP-5HE

ABL as part of the troposphere 3NABOS 2013 Arya, S., Introduction to Micrometeorology, 2001 (1) ABL structure

4 ABL structure over land surfaces in mid-latitudes NABOS 2013 Stull, R.B., An Introduction to Boundary Layer Meteorology, 1997 (1) ABL structure

Surface energy balance over land Oke, T.R., Boundary Layer Climates, 1897 NABOS (1) ABL structure

Surface energy balance over water Oke, T.R., Boundary Layer Climates, 1897 NABOS (1) ABL structure

Surface energy balance over snow Oke, T.R., Boundary Layer Climates, 1897 NABOS (1) ABL structure

8NABOS 2013 Chapter 2 1. ABL structure, a quick overview 2. Turbulence in the atmosphere and ocean 3. Measuring Temperature Profiles in the ABL 4. MTP-5HE

Dissipation 9 How to make Marie stir my tea 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)? (2) Turbulence

Kolmogorov theory on turbulent energy cascading Left: Vallis, G.K., Atmospheric and Oceanic Fluid Dynamics, 2006 Right: Grant et al., 1962 Lewis Fry Richardson: Big whirls have little whirls, that feed on their velocity. And little whirls have lesser whirls, and so on to viscosity. (2) Turbulence

Modelling techniques Reynolds averaged numerical simulation (RANS) Large Eddy Simulation (LES) Direct Numerical Simulation (DNS) (2) Turbulence

12NABOS 2013 Chapter 3 1. ABL structure, a quick overview 2. Turbulence in the atmosphere and ocean 3. Measuring Temperature Profiles in the ABL 4. MTP-5HE

13 In-situ techniques Meteorological towers Radiosoundings Teathered Balloons RPAS Measurement stations along the slope of mountains NABOS 2013 (3) Measuring temperature

14 Remote Sensing Techniques Sound Detection and Ranging-Radar Acoustic Sounding System (SODAR-RASS) Microwave Temperature Profiler (MTP) NABOS 2013 (3) Measuring temperature

1. ABL structure, a quick overview 2. Turbulence in the atmosphere and ocean 3. Measuring Temperature Profiles in the ABL 4. MTP-5HE Chapter 4

16 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 NABOS 2013 (3) MTP-5HE

17 Data Reliability NABOS 2013 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

18 Filtering I NABOS 2013 Esau, Wolf et al., 2013, in print (3) MTP-5HE Inter-comparison of all temperatures at the AMS and MTP-5HE at the heights of the AMS for |v| > 5 m/s

19NABOS 2013 Esau, Wolf et al., 2013, in print (3) MTP-5HE Top panel: MTP-5HE measurement during precipitation. Lower panel: rain rate measured with rain radar Filtering II

20 Filtering NABOS 2013 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

21 Thank you for your attention NABOS 2013