Commission for Instruments and Methods of Observation Fourteenth Session Geneva, 7

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Commission for Instruments and Methods of
ObservationFourteenth SessionGeneva, 7 14
December 2006

• INSTRUMENTS AND METHODS OF OBSERVATION FOR
  SURFACE MEASUREMENTS
• (OPAG Surface)
•  
• surface technology and measurement techniques
• (ET-STMT)

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Major topics

• Automation of visual and subjective observations
• Information on available instrumentation and
  instrument development
• Measurements in harsh environments
• Design, layout and representativeness of weather
  stations
• Urban and road meteorological measurements
• Cost reduction

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Major topics

• Automation of visual and subjective observations
• Information on available instrumentation and
  instrument development
• Measurements in harsh environments
• Design, layout and representativeness of weather
  stations
• Urban and road meteorological measurements
• Cost reduction

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Automation of visual and subjective observations

• Automation of manned observations
• Low impact on instrument measurementsbut
  quality assurance siting is critical
• Uniform and standardized determination of
  Present/Past Weather (visual subjective
  observations) remains unsolved
• Observing the weather is more than measuring a
  set of variables

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Automation of visual and subjective observations
Quality assurance
Ref. World Climate Data and Monitoring
Programme, WCDMP-52 (GUIDELINES ON CLIMATE
OBSERVATION NETWORKS AND SYSTEMS) (Photo
Meteorological Service of Canada)
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Automation of visual and subjective observations

• Layout of a station

Manual on the GOS Layout of an observing station
in the northern hemisphere showing minimum
distances between installations (Source UK
Meteorological Office, Observer's Handbook, 4th
edition, 1982)
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Automation of visual and subjective observations

• Siting exposure
• Intercomparing MAN ? AUT

• Representativety

Ref. World Climate Data and Monitoring
Programme, WCDMP-52 (GUIDELINES ON CLIMATE
OBSERVATION NETWORKS AND SYSTEMS) (Photo
Meteorological Service of Canada)
(Photo Finnish Meteorological Institute,
Finland)
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Automation of visual and subjective observations

• Representativety
• Layout of a station
• Siting exposure
• Intercomparing

Documented inCIMO Guide, IOM reports.
Like with instrument measurements to provide the
traditional physical variables, like temperature,
pressure, wind, etc. In fact increased flexibility
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Automation of visual and subjective observations

• However
• Assessment of the state and development of the
  atmosphere, and of significant weather

Remains critical, i.e. Subjective observations or
qualitative data has to be converted into
quantitative data or variables
To be able to generate requested information
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Automation of visual and subjective observations

• How to register quantitatively specific weather
  phenomena on remote distance, like
• significant phenomena (thunder, obscuration,
  showers, fog patches or whirls in the vicinity)
• different mixtures of precipitation types and
  intensities, inclusive freezing, blowing,
  drifting
• cloudiness not only coverage and cloud base, but
  also cloud type like cumulonimbus to indicate
  convection (e.g. CB, CTU)
• How to encode all these phenomena

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Automation of visual and subjective observations

• Introducing
• appropriate models describing the present state
  of the atmosphere
• sophisticated algorithms, linking various
  variables

easyuniform
complexdivers
convert the data into information
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Automation of visual and subjective observations
Conversion matrix (example) INPUT Data
PhysicalVariables
Weather
via database
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Automation of visual and subjective observations
ET/AWS-2006 (functional specifications)
I Instantaneous 1-minute value (instantaneous
as defined in WMO-No.8, Part II, paragraph
1.3.2.4) V Variability Average (mean),
Standard Deviation, Maximum, Minimum, Range,
Median, etc. of samples those reported depend
upon meteorological variable T Total
Integrated value during defined period (over a
fixed period(s)) maximum 24 hours for all
parameters except radiation which requires a
maximum of one hour. A Average (mean) value.
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Automation of visual and subjective observations

• Quality evaluation and assurance of automated
  subjective observations
• measurement uncertainty of a quantitative
  variable is not applicable
• perfomance indicators, using a contingency
  matrix

detector yes noreality yes a b no c d
ESS Equitable Skill Score POD Probability of
Detection FAR False Alarm Ratio
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Automation of visual and subjective observations

• Quality evaluation and assurance of automated
  subjective observations
• measurement uncertainty of a quantitative
  variable is not applicable
• perfomance indicators, using a contingency
  matrix

detector yes no reality yes 15 5 no 5 8
0
ESS 75 POD 25 acceptable? FAR 69
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Automation of visual and subjective observations

• Items to be solved
• How to calibrate (up to source) a
  multi-parameter followed by algorithm?
• What is an appropriate (set of) reference(s)
  (human observations are subjective)?
• Can a reference be made traceable to any
  standard?
• Is regional climate relevant (arctic, tropic,
  mountaneous, deserts)?

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Information on available instrumentation and
instrument development

1. Instrument Development Inquiry(IDI- 7 published,
   IDI- 8 to be issued)
2. World Meteorological Instrument Catalogue (CMA)
   on CD
3. HMEI Members Product Catalogue via the Web (see
   INF. 9)
4. Web Portal on Development, Maintenance and
   Operation of Instruments, Observing Methods and
   AWS (CIMO homepage)
5. Other (CIMO Guide, IOM reports)

OPAG CBissues
HMEI Association of Hydro-Meteorological
Equipment Industry
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Information on available instrumentation and
instrument development

• Instrument Development (only) Inquiry(now every
  4 years)(IDI- 7 published, IDI- 8 to be issued)
• IDI-reports published
• Like IDI-7 (IOM Report No. 93, WMO/TD No. 1352)
• Or / and
• As Web Portal, updated regularly, to be
  up-to-date.

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Measurements in harsh environments

• Most instruments are designed for use in moderate
  climate zones, although requirements are valid
  for all climate zones.
• Special attention shall be given to
• Harsh environments (arctic, tropic, desert,
  mountains)
• Severe weather
• Actions
• Extend of definitions and requirements on
  measurements in severe weather conditions.
• HMEI members are encourage to develop ..
• Intercomparisons have to be organized for further
  evaluation

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Measurements in harsh environments
Source Eumetnet Severe Weather Sensors Project
no. 2
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Measurements in harsh environments

• Extend of definitions and requirements on
  measurements in severe weather conditions
• Rec. 4.1/1
• The CIMO Guide be expanded to include
• a. A definition of the siting characteristics of
  the Automatic Weather Station in terms of local
  icing conditions, and
• b. The requirements for measurements in severe
  icing conditions.