World Meteorological Organization Working together in weather, climate and water Joint Meeting of CBS EXPERT TEAM ON SURFACE-BASED REMOTELY-SENSED OBSERVATIONS (First Session) and CIMO EXPERT TEAM ON REMOTE SENSING UPPER-AIR TECHNOLOGY AND TECHNIQUES (Second Session) WMO Report on the suitability and operational aspects of microwave radiometry (MWR) By Dr. Arkadi Koldaev, Central Aerologicval Observatory, Roshydromet (Russia) CIMO, TECO WMO “Mobile System for Remote Sensing of Wind, Humidity, Temperature and Precipitation Microstructure Profiles during Special Events and Sport Competitions” By Alexander Gusev, Viktor Ignatov, Arkadiy Koldaev, Sergey Sarychev. Roshydromet

2 List of Contents WMO 1.Introduction 2.System construction 2.1.General overview 2.2.External sensors 2.3.Operator cabin 2.4.Supplement Equipment 3.System operation 3.1.Radar wind profiler 3.2.Microwave temperature\humidity profiler 3.3.Micro Rain Radar MRR-2 4.Summaries CIMO, TECO

WMO 1.Introduction 3 CIMO, TECO Meteorological support of the special events became more and more desirable. - Practically all kind of open air competitions are depended on the wind, precipitations and current snow surface conditions. - Upper air soundings can provide local small range NWP models with the fresh data flow, which makes the results of NWP much more valuable. - Who and how will operate with meteorological instruments after the event end. - The system for remote radar wind profiling and remote microwave radiometer temperature and humidity profiling during Sochi 2014 Winter Olympic Games were decided as “temporary” - The mobile installation can be easy exploit after the Sochi 2014 for weather service of the other special events. - Taking into account the synoptic situation, it is always possible to move and install the system on the position in front of general atmosphere motion. - But, such a strategy creates additional difficulties in obtaining of the information with satisfactory quality.

4 2.1.General overview WMO Microwave temperature/humidity profiler Micro Rain Radar MRR-2 Side lobe suppression screen electric power engines (gasoline operated) trailer operator cabin CIMO, TECO

5 2.2.External sensors WMO Scintec RPG MRR-2 CIMO, TECO

6 2.3.Operator cabin. WMO Diagnostic monitor Digital decoder- controller of azimuth ENIGMA signal Processor Data processing notebook Special Monitor full internal diagnostics Wind profiler processing system DC power supply CIMO, TECO

7 2.4.Supplement Equipment WMO electric power engines Azimuth rotator Data processing notebook GPS GSM Mini-weather station CIMO, TECO

8 3.1.Radar wind profiler WMO CIMO, TECO Operating Frequency 800 to 1400 MHz, typically 915, 924, 1280, 1290, 1299, or MHz. Maximum Average RF Power 100 W avg. Antenna typeElectrically steerable phased array Aperture Nominally 3.0 m2 Direction Zenith and ± 15.5° Gain ~26 dBi Beam width ~9° Minimum measurement height(1) 120 m Maximum measurement height(2) 2 to 5 km Wind speed accuracy < 1 m/s Wind direction accuracy < 10º - Wind profiler is operating at the frequencies which are very near the cell phone operation. - For each location it is possible to minimize the influence of the noise by adjusting of the azimuth direction of the radar antenna. -For this purpose, the antenna was supplied with the azimuth rotating assembly. - The azimuth position with the minimum signal is decided as optimal one. - Operating in the mountain environment is probably most complicated from this point of view: if one “near the ground” side lobe is looking to the hill, other one is looking in the space at the sufficient height. - The main purpose for application of the screens is in suppression of the reflection from the “near the ground” side lobes.

9 3.2.Microwave temperature- humidity profiler WMO CIMO, TECO Sampling Rate1 second Antenna beam resolution 3.5° (Hum. Profiler), 1.8° (Temp. Profiler) Boundary Layer Temperature resolution 50 m Boundary Layer Temperature accuracy 0.25 K RMS Time for absolute calibration 2 minutes Long term TB drift0.2 K / year Channels9, fixed, parallel scanning Time resolution1 second Radiometric Noise [10 sec. integration time] 0.06 K RMS Thermal receiver stability0.03 K - Microwave temperature\humidity profiler is operating at the wide range of frequencies. -But for microwave profiler there is other principal limitation. - The physical principle of temperature and humidity profile retrieval is based on the assumption about “layer uniform” atmosphere. - It can be recommended to use for the measurements kind of flat fields between hills, with sufficient horizontal dimensions (more than 5 km), or perform measurements along the mountain slope. - As far the retrieving algorithm is using calculation of the absorption in the oxygen depending on the pressure, thus it is necessary not forgotten to implement the correction of the height of real measurements.

Micro Rain Radar MRR-2 WMO CIMO, TECO TopicMRR-2 Working frequency24 GHz Modulation typeFM-CW Transmitted power50 mW Antenna diameterø 60 cm Doppler spectra m/s (ø mm Outputsrain rate Indication“Bright Band” height Height range m, Number of height intervals30 - Micro Rain Radar MRR-2 is looking striate in zenith direction, and thus does not have any specific problems operating in the mountain environment. - The electromagnetic interference at the operating frequency is also not too often, and if it happens, just necessary to wait for a while, because such an interference are very short in time.

11 4.Summaries WMO CIMO, TECO The Mobile System for Atmosphere Remote Sensing (MS ARS) was developed and constructed. The system is ready for measurements of Wind, Humidity, temperature and Precipitation Microstructure Profiles in field conditions. -The main limitations for field operation of MS ARS were discussed, and preliminary recommendations to overlap these limitations were elaborated. -The final instructions for proper operation of the system in mountain environment can be done after inter comparisons of the data with radiozonde profiles.

Thank you ! Dr. Koldaev CIMO, TECO