SESSION 1 - NEW DEVELOPMENTS AND OPERATIONAL EXPERIENCE WITH SURFACE OBSERVATION TECHNOLOGY AND NATIONAL NETWORKS

Keynote 1 - How do we maintain sustainable high-quality climate observation networks that can answer the question: How has the climate changed over the past 50 years? - Bruce Baker, USA (See document here)

This presentation looked at the necessity for the weather, environment and climate community to maintain an observing system capable of detecting and documenting global climate variability and change. Mr Baker noted that, as there is compelling evidence that the climate is changing, the degree, nature and cause of the climate variations and establishing whether there is in fact a change requires solid information. To clarify this it will be necessary to have:

• improved observations of the state variables and forcings,

• the means to process these and understand them,

• the ability to set them in a coherent physical (and chemical
  and biological) framework with models.

Ten climate monitoring principles that should be applied to climate monitoring systems were noted:

• Management of Network Change

• Parallel Testing

• Metadata

• Data Quality and Continuity

• Integrated Environmental Assessment

• Historical Significance

• Complementary Data

• Climate Requirements

• Continuity of Purpose

• Data and Metadata Access

Mr Baker looked at various examples of modernization of the USA climate network and showed some of the the pilot projects being carried out in the USA.

The presentation stressed the need to : standardize international Climate Monitoring Networks; develop international test beds to evaluate new technology; look at the regional impacts on environment, human activities and sectors such as agriculture, energy, fisheries andwater resources.

Mr Baker also noted the need for a common entry point for monitoring of climate state variables on a global scale.

Representativeness Evaluation of China’s National Baseline Climate Station Network - Dr Jianxia Guo - China (See document here)
Dr Guo's report noted that although China has 65 climate regions, China still has 1 climatic zone, 4 climatic sub-zones and 18 third-order climatic regions with no baseline climate stations. Considering this is urgent to optimize the distribution of the current baseline climate station network in China. Dr Guo's presentation outlined in further detail the climate station network situation in China, with the conclusion of the paper outlining points to rectify this.

Recent developments and plans in Finnish Meteorological Institute (FMI) Observation Services by 2015 - Dr Keijo Leminen - Finland (See document here)
This presentation considered the FMI surface weather station network, consisting of nearly 200 sites. FMI intends to make all its observation stations automatic by 2015.

FMI Observation Services has developed and implemented a customer process starting in 2004 This article describes the customer process and provides insight for its development. Also the presentation outlines what kind of changes are expected in the FMI Observation Network by 2015.

Total Ozone Monitoring by Ground Based Instruments as Part of GAW - Dr J. Staehelin (See document here)
Ozone measurements by ground based sun photometers (wavelength region: 305-340 nm) are part of the regular measuring program of Global Atmosphere Watch (GAW) of WMO. Although the global ozone layer is also monitored from space since the 1970s, instruments operated from satellites have limited lifetimes. The design of the ground based networks and their operations was  presented, particularly the European Network.

The two methods for the ground based measuring of ozone use the Brewer and Dobson type instruments. Since the Montreal Protocols were introduced, ozone depleting substances have reduced significantly. This has caused global ozone amounts to also decrease dramatically, but recent modeling results indicate that total ozone will increase and it is therefore important to continue high quality ozone observations. It is recommended to use a combination of both technical to continue monitoring ozone.

Keynote by CIMO President  - Future challenges for CIMO, illustrated with examples of upper-air systems Intercomparisons and testbeds - Dr John Nash, UK
CIMO Activities
Dr Nash noted that WMO Members had expressed a desire for CIMO to expand its activities into Oceans, Hydrology and so forth. He further noted that CIMO should be the facilitator for certain essential tasks within WMO, specifically:

• CIMO should help national experts in different regions of the world to share ideas, experiences and find ways to collaborate effectively.

• CIMO should facilitate improved collaboration between technical experts and researchers and manufacturers.

• CIMO should develop and in a timely fashion provide and update information in the CIMO guide.

Advantages from CIMO Intercomparisons
Dr Nash then went on to look at various Upper-Air Intercomparisons that have been carried out in recent and previous years. From these examples Dr Nash illustrated the effectiveness of Intercomparisons for identifying and resolving various instrument problems and issues. The illustrations demonstrated that currently tested Radiosondes, show that the instruments are now much closer in accuracy with significant reductions in inconsistencies of the various measurements that Radiosondes record. This is for the most part due to the cooperation of manufacturers and WMO at Intercomparisons.

Dr Nash also encouraged individual countries, research institutes and met offices to inform WMO of Intercomparisons they may conduct in or that the information could be disseminated by WMO to the wider interested communities .

Dr Nash outlined the ongoing need for WMO to conduct further large scale Intercomparisons and gave a list of those he forsaw in the short to medium term.

Test-beds
Testbeds can be used for long-term testing, over a longer period of time, or for a series of testing, compared to the temporary set-ups that have been used for previous Intercomparisons in various situations. With a permanent testbed many different measurements can be compared, simultaneously over a long period. Testbeds also give the ability to discover an optimal density of observations for a specific need.

On the issue of co-ordination, Dr Nash noted that good working relationships with HMEI had been established and renewed on an ongoing basis by working together on:

• Radiosonde Intercomparisons

• Training workshops,

• Documentation and

• Cc-operation with GCOS scientists  in developing the GCOS upper-air network.

• Dr Nash expressed the hope that working together with HMEI on testbed results and evaluations will bring together a still wider range of experts.

Keynote 2 - Solid Precipitation Measurement - Ms Rodica Nitu, Canada (See document here)
Ms Nitu noted that the last WMO Intercomparison of this type of measurement was 20 years ago.

The CIMO Guide on precipitation measurement was outlined to the meeting. Ms Nitu emphasized that the metadata of the conditions of the measurements and the instrument used, as well as the actual measurement, were essential for determining the quality of the measurement.

The Expert Team on Surfaced-based Instrument Intercomparisons and Calibration Methods was asked to assess the methods of measurement and observation of solid precipitation, snowfall and snow depth at automatic unattended stations used in cold climates (polar and alpine).

There was a 2008 survey on the measurement and observation of solid precipitation by AWS, which 54 WMO members (46% of gobal land mass)reponded; 35 oparticipants (28% of gloabal land mass) monitor solid precipitation. Of the total, 18% of the sites have automatic instruments. For automatic instruments used for measuring total precipitation amount, tipping bucker rain gauges (TBRG), were 82.9%; weighing gauges (WG) were 16.2%; with optical sensors, 0.4%; and “level” gauges, 0.5%. The 2008 survey showed that for Weighing Gauges, 6 models from 6 manufacturers were used and for Tipping Bucket type instruments, 28 models from 22 manufacturers were used. Various methods and strength of  heating were used and about 28%of instruments used either single or double wind single shields.

Considering the wide variety of methods and configuration of instruments a 2008 the Meteorological Service of Canada (MSC) initiated a qualitative assessment of current precipitation gauges measuring precipitation amount, liquid and solid, covering a large spectrum of measuring principles and constructive parameters in use. See the document for a detailed report on the Intercomparison.

The instruments evaluated and their configuration is given in the table "Precipitation Gauges and their configurations, CARE experiment 2008/2009" below:

Ms Nitu proposed a CIMO Intercomparison of solid precipitation measurement instruments in their configuration used in the field. with the following objectives:

• evaluate and report on the performance of the instruments and methods in field conditions;

• evaluate and provide guidance on the operational configuration of automatic gauges (e.g. use of heating, use of windshields, height of installation, redundancy), to achieve data consistency;

• assess the feasibility of developing multi-parameter algorithms to improve the quality of precipitation data reported from an Automatic Weather Stations;

• provide datasets to support studies on the homogeneity of long-term records of precipitation with special consideration given to solid precipitation;

• enable the development of adjustment procedures of the systematic errors of precipitation measurements;

• establish the WMO field reference standard using recording precipitation gauges;

• provide feedback to manufacturers to enable the development of recording precipitation gauges, addressing known limitations;

• draft recommendations for consideration by CIMO.
   

Development and Challenges in SWISSMETNET,  the New Swiss Meteorological Network - Dr A. Roulet, Switzerland (See document here)
This is a meteorological (Nowcasting) and climatological (Climate Change) network. It is high density network and it uses cell phone technology communications for reduced costs. It is an example of a a state-of-the-art unified and secured network. It is pecifically configured for Swiss conditions and needs. It also allows for an extended network of AWS.

Extention and Development of the Surface Obnserving Network of the National Meteorological Service of Morocco - Nabil Nouni, Marocco (See document here)
In light of disastrous extreme weather events, particularly floods, in Morocco in the last decade, the Moroccan department of meteorology has established a program to improve early weather warning. This presentation outlined the progress that the Moroccan  Met. Service has made to date.

The improvements in the Moroccan national weather observation network (the VIGIOBS project) being implemented during the period 2010-2012 include: ninety automatic climatological stations, sixty automatic synoptic stations and six mountain automatic weather stations.

The presentation outlined several challenges that were identified for the Moroccan automatic weather station network:

1. Low density of the network and bad distribution;

2. Variety of data storage format;

3. Lack of automatic transmission solution of the observed data;

4. Not automatic coding meteorological message of observed data in accordance with WMO;

5. Data transmission require in most cases human intervention and the passage through other local treatment system;

6. Data transmission iwas done by technical means that are becoming obsolete and expensive - the analogue leased lines.

The VIGIOBS project, which addresses these issues for a better distribution of the Moroccan observation network, a high availability of data for their easy storage and treatment at end of climate studying and weather forecasting, is described in the presentation of the document.

Laboratory and Field Evaluation of the NubiScope - Dr Wiel Wauben, Netherlands (See document here)

This paper documents the Royal Netherlands Meteorological Institute (KNMI) evaluation of the NubiScope, a scanning pyrometer, for cloud observations. The KNMI currently uses ceilometers for automated cloud reports. However as major limitation of the automated cloud observations using ceilometers is the lack of spatial representativeness, KNMI purchased and evaluated the NubiScope for cloud observations.

SESSION 2 - Upper-air and Remote-sensing Observing Technologies and Systems

Keynote 1 -The Radar Quality Control and Quantitative Precipitation Estimation Intercomparison Project (RQQI) - Mr Paul Joe (See document here)
The presentation outlines the progress, potential and problems that radar technology has for weather prediction. Dr Joe then went on to outline the proposed RQQI.

The RQQI will be held in the UK. It will evaluated the various methods, procedures and algorithms used in Radar measurements, to determine which are technically superior.
The evaluation will look at:

• Ground clutter removal

• Resolving of anomalous propagation echoes

The project will look at finding the most useful methods and techniques and give feedback for users and manufacturers in regard to Radar performances.

  Advancements in the AMDAR Humidity Sensing - David Helms, USA (See document here)
This presentation briefly describes the WMO Aircraft Meteorological Data Relay (AMDAR) Program and then goes on to document the progress for AMDAR to add measurement of water vapor from commercial aircraft to its portfolio.  Spectra Sensor a HMEI member has been working with the NOAA National Weather Service (NWS) to carry out factory tests of water vapor sensors. Also
independent chamber tests were conducted by the German Weather Service (DWD)  and NWS, culminating with reports in September 2009 and October 2009, respectively.

Update on the European Weather Radar Co-operation (Opera) - Asko Huuskonen, Finland (See document here)
This document recaps the tradition of weather radar collaboration at the European level, which dates back to COST 72 in 1991 and the subsequent establishment of OPERA in 1999.

OPERA has the objective to ”To harmonize and improve the operational exchange of weather radar information between National Meteorological Services” and has 30 European members. The presentation outlines the projects of the OPERA programme and looks at a the most recent phase of the OPERA project, the creation of the OPERA Data Center, which is planned to start
operation early 2011.

Upgrade of the Indian Radiosonde Network: Performance and Future Plans - Mr G. Kumar, India (See document here)
The India Meteorological Department (IMD) is operating a network of 39 Radiosonde/Radiowind stations, which it is in the process of modernizing. IMB has adopted a strategy to replace obsolete systems, with, In the first phase of modernization, ten stations being upgraded with new GPS based Upper air systems in 2009. ECMWF has validated that the data from the new stations has considerably improved in quality.

In 2010 India plans that 14 further stations are to be upgraded. Further GPS Radiosondes along with a 1680 MHz ground system, acquisition & processing software has also been developed indigenously. The standards of data quality required by the Numerical weather Prediction (NWP) centers, which has been achieved at the upgraded 11 stations, will be extended to 24 stations including 5 GUAN stations after ensuring operational performance and data quality. After this the remainder of the Indian network will be upgraded also.

The document describes the upgrading of the Indian network. Dr Nash commented from the floor, after the presentation, that it was a good achievement for India and that CIMO was pleased to see these improvements in India's data.

On the Generation of an Optimized Fractional Cloudiness Time Series Using a  Multi-Sensor Approach - Dr Wiel Wauben - Netherlands (See document here)
This paper describes the active and passive remote sensing techniques that observe clouds, which are operated nearly continuously at the Cabauw Experimental Site for Atmospheric Research [CESAR]. The Intercomparison of these techniques was of a 1-year data set.

The instruments involved are: 2 types of ceilometers a Vaisala LD40 and a Vaisala CT75K), including the sensor that is used operationally by KNMI for generating the automated cloud observations; a cloud radar (a Degreane 35 GHz radar); an infrared pyrgeometer (Kipp & Zonen, CG4); a scanning pyrometer (a NubiScope system, manufactured by IMK/Sattler-SES), and a total sky imager (YesInc, TSI-440).

Results indicated that the indicating that the Observer data are systematically different than those from the instruments. The most important conclusion was drawn from this paper was that for fundamental climate data records and their associated essential climate variables, such as fractional cloudiness, it is of the highest importance to properly manage the change from one observing technique to the next.

Keynote 2 - Wind profilers radars (COST Wind Initiative for a Network Demonstration in Europe: CWINDE network) - Dr Volker Lehmann, Germany (See document here)
The current Global Observing System (GOS) for the atmosphere consists of a mix of ground and space based components, with a large part of them being remote sensing instruments. The paper notes the unique ability and advantage of Wind Profile Radars (RWPs) in their ability to provide vertical profiles of the horizontal wind at high temporal resolution under almost all weather conditions.

The document paper gives a brief overview of the technical fundamentals of RWPs, The paper then goes on to discuss some important practical aspects of the operational application of RWP’s and the global operational use of RWPs.

The predominant advantages that the RWP has over other types of wind profiling are:

• Low cost per measurement

• Good measurements in clear and cloudy conditions

• Unattended automatic system

Main Disadvantages :

• The instrument's sensitivity to cluttering

• Interference that can occur
   

Recent Improvement of the Integrated Observation Systems (IOS) in Japan - Kenji Akaeda, Japan (See document here)
This paper details the following IOS improvements at the Japan Meteorological Agency (JMA):

• JMA has a nationwide weather radar observation network of 20 radars, all remotely controlled centrally from JMA’s headquarters in Tokyo; with 16 of the radars  recently upgraded from conventional to Dopplar radars.

• JMA has also completed the upgrading of its upper-air observation systems using GPS radiosondes at all 16 of its upper-sounding sites, 8 of which are operated with Automatic Balloon Launchers (ABLs).

• In the area of automatic surface wind observation, uses the AWS network called AMeDAS (Automated Meteorological Data Acquisition System), In 2008 JMA started using a new AMeDAS capable of observing maximum instantaneous wind speeds as well as 10-minute average wind speeds.

• JMA started operational use of operational processing of integrated water vapor (IWV) data in Numerical Weather Prediction (NWP) in October 2009.

• At the end of May 2010 JMA started to issue new information related to nowcasting on tornadoes and lightning. 

Monitoring of Eyjafjallajðkull ash layer evolution over Payerne Switzerland with a Raman Lidar - Dr Todor Dineov, Switzerland (See document here)

Experimental Study of Rain-Induced Accuracy Limits for Microwave Remote Temperature Profiling - Dr Arkady Koldaev, Russia
This paper documents the field tests, in Russia at the Obninsk World Meteorological Centre, during the summer season 2009 of  carried out to discover information on the influence rain precipitation has on microwave measurements of the temperature profiles.

Lapbiat Atmospheric Sounding Campaign in 2010: Upper-Air and Remote Sensing Observations of Water Vapor - Rigel Kivi, Finland (See document here)
The Lapland Atmosphere-Biosphere Facility (LAPBIAT) campaign took place in Sodankylä, northern Finland. The campaign compared upper-air and remote sensing instruments measuring water vapor and stratospheric aerosols in the Arctic vortex in early 2010.

The aim of the campaign was to access accuracy of measurements of water vapor in the upper troposphere and lower stratosphere (UTLS), which are needed for climate studies

The campaign instruments involved were as follows:

• Balloon borne research grade water vapor instruments such as the Cryogenic Frostpoint Hygrometer (CFH) and the Lyman- alpha fluorescence hygrometer FLASH-B.

• The climate research Radiosonde Vaisala RR01, whch is currently under development, in the same payload with the cryogenic frost point hygrometer and the fluorescence hygrometer.

• Remote sensing instruments included the microwave radiometer for water vapor measurements MIAWARA-C.

• Aerosol in-situ profile measurements were made by the new COBALD instrument and by a well established balloon borne aerosol backscatter sonde.

• Particle measurements in the stratosphere were made simultaneously with the water vapor measurements.

SESSION 3 - Instruments Comparisons and Testbed Experiments

Keynote1 - The WMO Field Intercomparison of Rainfall Intensity in Vigna di Valle - Dr Emanuele Vuerich, Italy (See document here)
This paper was the report to CIMO of the Intercomparison of rain gauge instruments in 2009 in Italy,which several HMEI members participated in and the results of which have been previously presented to members in previous HMEI newsletters.

The paper also offers a discussion on the proposed recommendations and possible developments in the standardization of RI measurements and laboratory calibration procedures at the international level in order to obtain homogeneous and compatible data sets. There were 18 recommendations resulting from this Intercomparison, see the document for these, which will be discussed at the CIMO sessions at Helsinki immediately following the TECO at which this report was presented.

In the presentation of this report Dr Vuerich noted the participation and help of HMEI at the pre-Intercomparison set-up meeting and its reporting on the Intercomparison meetings

The NOAA/FAA/NCAR Winter Precipitation Test Bed: How Well Are We Measuring Snow? - Dr Roy Rasmussen, USA (See document here)
This testbed is a joint collaboration between NOAA, NCAR, NWS, and FAA to assess various solid precipitation measurement techniques. The experiment is being conducted at the NCAR Marshall Field research site. This type of assessment is considered critical for any ongoing studies and applications that rely on accurate and consistent precipitation measurements, particularly for Aviation and Climate needs.

The presentation notes that the most recent comprehensive study, the “WMO Solid Precipitation Measurement Intercomparison” concluded in 1998 , focusing on manual techniques. Precipitation gauge technology has changed considerably in the last 12 years and the focus has shifted to automated techniques. 17 gauges/configuration of gauges from 5 manufactures, Belfort, Hydrological Services, OTT, GEONOR, and Yankee were looked at in the experiment carried out over the last three years and still ongoing.

Studies of airflow around the shields were carried out, both with field studies using sonic data and also using laboratory and modeling studies.

In addition to gauge studies, NCAR has been actively evaluating the use of visibility to estimate snowfall intensity. A study was undertaken at the National Center for Atmospheric Research (NCAR) Marshall Field Site to compare the ASOS algorithm for precipitation intensity (visibility-based) to actual liquid water equivalent (LWE) rates. This was carried during the 2007-2008 winter season.

Some points from the experiment, that Dr Rasmussen talked about during his presentation of this report at TECO, were:

• Visibility is not an accurate measure of precipitation rate due to the large amount of scatter in the comparison of the data sets.

• Shielding against updraft of snow is an ongoing problem for many instruments.

Investigations into the improvement of Automated Precipitation Type Observations at KNMI - Mr Marijn De Haij, Netherlands (See document here)
The Royal Netherlands Meteorological Institute (KNMI) employs the Vaisala FD12P present weather sensor for automated observations of visibility, precipitation type and duration in the national meteorological observation network, however weaknesses in this instrumentation regarding precipitation observation have become evident. Therefore a field test with the Thies LPM, Ott Parsivel, Lufft R2S and Vaisala WXT520 sensors started in De Bilt in September 2008 to investigate other sensors for potential use in observing precipitation.

Improving Reliability and Sensitivity of a Laser Snow Depth Gauge - Dr E. Lanzinger, Germany (See document here)
This paper looks at the new laser snow depth gauge JENOPTIK SHM30, which has been tested during two winter seasons at Deutscher Wetterdienst (DWD), incomparison with the operationally used ultrasonic snow depth gauge CAMPBELL SR50G . Its measurement accuracy has proven to outperform ultrasonic snow depth gauges by almost one order of magnitude. However even the Jenoptic instrument has problems with automatic snow depth measurements occuring at small snow depths and especially at the onset of snowfall which is a crucial information e.g. for road weather service.
This paper compares the different methods of the two instruments and concludes and suggests improvements as follows.

In favor of the laser method:

• Lower measurement uncertainty by almost one order of magnitude.

• Evaluation of the backscatter signal allows sensitive detection of snow cover and reduces the false alarm rate for the first few centimetres of snow significantly.

• No influence of temperature and wind.

• Practically no zero drift.

• No outages even during heavy snowfall.

• No cross bar needed due to measurement at an angle of 10° to 30°.

• Very little maintenance needed.

Laser snow depth gauges could be further improved by:

• Calibration and adjustment of the characteristic curve of the backscatter signal in order to define a common threshold for the detection of snow cover.

• Integration of an auto-zero function to automatically correct for any changes of the zero level that are not caused by snowfall.

• Adequate heating of the housing to keep the optical path free of ice accretion.

• Making the laser beam invisible for animals, especially for birds (as they chase the laser and cause problems), either by a change of the pulse width and repetition rate ratio or by using an invisible wavelength.

• The omnipresent problem of point measurement could be solved by a scanning laser gauge that would allow simultaneous measurements of snow depth at several places.

Results of the WMO Intercomparison of Thermometer Screens/Shields and Hygrometers in Hot Desert Conditions - Ms Muriel Lacombe (See document here)
The campaign was held at the meteorological station of Ghardaïa, Algeria. A group of 29 screens/shields both artificially-ventilated (7 different models) and naturally-ventilated (11 different models) and 17 humidity sensors (8 different models) were involved in this Intercomparison held for 12 months in 2008/2009. Ten of the manufacturer participants in this Intercomparison were HMEI members.

This document is the PRELIMINARY results only, the fully informed report will be released by WMO before the end of 2010.

Some preliminary results for screens noted:

• Nearly all small naturally ventilated screens are warmer than the reference.

• Artificially ventilated screens are not significantly cooler.

• Large Stevenson screens are very close to the reference.

Some Some preliminary results for hygrometers:

• 5 models gave very good results 98% within +/- 3% of the reference.

• 2 models stayed within 4% deviation.

• 1 model showed larger deviations.

It should be noted that the sensors designated as SCAE which appear to have (quoting from the presented document from TECO) "showed a drift greater than 1.5%"; "showed large deviations" and other such comments, only appear thus because of problems with the sensors NOT having been set-up at the Intercomparison according to the manufacturers instructions.

Keynote 2 - Outcomes from the COST Action ES0702: European Ground-Based Observations of Essential Variables for Climate and Operational Meteorology (EG-CLIMET) - Anthony J Illingworth, UK (See Power-point presentation here)
This COST action has been set up to investigate instrumentation that can provide high resolution data for the new high resolution models.

The variables of interest for this COST action are: wind; temperature; humidity; cloud; average ice-water content and volcanic ash measurement (aerosols). The COST group recognized that recent advances in the ground based remote sensing instruments, for theses variables, promise that they will become inexpensive, low maintenance and able to operate automatically unmanned.

The COST Action ES0702 has set up 4 working groups to investigate respectively the following:

• Individual instruments;

• Instrument combinations;

• Optimal network density

• Data assimilation.

In regard to current remote instrument developments, it was seen from operational and experiments that:

• Wind profilers are a well developed technology, but still have some problems (such as bird echoes).

• Microwave temperature instruments are reasonably good.

• Ground clutter from Radar can be used to detect low level moisture.

• Clouds can be detected by Cloud Radar, Lidar and Radiometers

• There is currently testing for FM/CW Radars for cloud detection.

• Lidar ceilometers are widespread technology currently.

• There is a new new generation of cheap unmanned Lidars measuring aerosols and volcanic ash.

• Raman N2 Lidar is hopefully coming soon for aerosols, also potentially for humidity measurement, but this is currently research only.

The issue of the whether expense of further Radar and Lidar developments, with further capacities, is required was a question to be posed to National Met Service representatives at the next COST meeting to be held 16-18 November 2010 in Koln, Germany.

Performance Assessment of China L band GTS1 Radiosonde - Wei Li, China (See Power Point Presentation here)
Dr Li's  gave a comprehensive PowerPoint presentation concentrated on the results of the three Chinese Radiosondes (which are used in the Chinese network of upper-air stations) that participated in the WMO Intercomparison at Yangjiang and which Intercomparison is discussed below in the next item.

Initial Results from the WMO Radiosonde Intercomparison, Yangjiang, China, July 2010 - Dr Nash, UK (See document here)
It should be stressed that this is a PRELIMINARY report of the field test phase of the China WMO Radiosonde Comparison that has been successfully concluded, and is only for the benefit of the CIMO meting. The work must now start in order to complete the final report on the Quality Radiosonde Systems and the relationship to SSI instruments; this is expected to be ready by March 2010.

Several HMEI members were participants in this Intercomparison Intermet, MODEM, Graw Radiosonde GmbH, Meteolabor, JIN YANG, MEISEI Co. Ltd, Vaisala, China HUAYUN, Lockheed Martin-Sippican, as well as other Chinese manufacturers. This Intercomparison, originally conceived as a Regional Intercomparison, but was then extended to be a major WMO International Intercomparison.

The Intercomparison was very successful and results in general appear to be pleasing for the quality of Radiosonde data, with very close agreement in measurements of all the parameters: pressure; temperature; humidity. Nevertheless, of course, there are still significant issues to be discussed and resolved, which will be in the Final Report of the Intercomparison. The information from the Intercomparison is of great use to the manufacturers involved. Also the Intercomparison results can be expected to lead to further refinement of planning for GRUAN and GUAN and Members operational networks.

Results from the Lindenberg Upper-Air Method Intercoparison (LUAMI)

• The Intercomparison between an airborne LIDAR with ground based instruments, as well as with in-situ measurements, demonstrated a high degree of consistency between these independent techniques.
• The ability of ground based instruments like microwave radiometers, GPS networks and Raman LIDAR for observing humidity profiles was demonstrated and proved useful tools for evaluation NWP products.
• The Radiosonde Intercomparison delivered a wealth of data for assessing the performance of different instruments. In the troposphere, the general agreement is within an average deviation of
  0.2 K and 5%RH for temperature and humidity, respectively. However, a number of issues have been identified, such a radiation effect on the temperature data in the stratosphere of various
  instruments and a dry bias of some instruments in the humidity measurements. Some of the issues observed during the campaign have already been addressed and fixed by the Radiosonde
  manufacturers.
• Useful data was gained with respect to atmospheric processes regarding the Frostpoint Hygrometer (CFH) and particle backscatter observations (COBALD) that are being used to study ice cloud formation conditions.

Please see the linked document for details of the experiments.

VÄISÄLÄ AWARD 2010 For an Outstanding Research Paper
Two papers were awarded this year:

• RAPID SAMPLING OF SEVERE STORMS BY THE NATIONAL WEATHER RADAR TESTBED PHASED ARRAY RADAR by Pamela L. Heinselman (USA) (see more at: http://journals.ametsoc.org/doi/abs/10.1175/2008WAF2007071.1)

• THE WMO FIELD INTERCOMPARISON OF RAINFALL INTENSITY (RI) GAUGES in Vigna di Valle (ITALY), October 2007- April 2009: relevant aspects and results by Emanuele Vuerich, (Italy), et al. (This paper was also the Keynote 1 paper of Session 3, linked above)

SESSIONS 4 & 5
These sessions dealt with matters mainly pertaining to issues for WMO Members and NMHSs. Where relevant these issues have been previously been informed to HMEI members in other reports.

SESSION 6 - ROUND TABLE DISCUSSION
The round table discussions were lively with suggestions and information for CIMO work in the future. Some comments were:

• EMETNET has a new Working Group on Instruments

• Many comments said that TESTBEDS were considered of considerable importance and there was a call for both National and International Testbeds to be set up.

• The meeting was informed that, following the Italian Intercomparison of Rainfall Intensity Instruments, the Swiss Meteorological Service had moved from Tipping Bucket measurement techniques to Weighing Gauge type instruments.

• Intercomparisons were generally agreed to be the vital work of CIMO.

• Canada announced its wish to host the Solid Precipitaiton Intercomparison .

• It was stated there is a need for an Intercomparison of Reference Instruments.

• The intertwining roles of BIPM-ISO-CIMO were stressed.

• An Internet search facility for the CIMO Guide online was requested.

• HMEI suggested that National and International Intercomparisons should have the same procedures and that this could be developed by CIMO and enshrined in the CIMO Guide, in order that full traceability for all Intercomparisons could be achieved.

• It was further suggested that there could be ISO standards developed for both National and International Intercomparisons. In this way manufacturers who had instruments measured at such Intercomparisons would be able to reference their instruments as validated to ISO standard assessments.

Closing of the conference
The conference was closed at 4pm on 1 September 2010.