Development of the USEPA Quality Assurance Guidance for the Collection of Meteorological Data Using Passive Radiometers

2011 National Air Quality Conferences March 7 - 10, 2011

Development of the USEPA Quality Assurance Guidance for the

Collection of Meteorological Data Using Passive Radiometers

Robert A. Baxter, CCMT&B Systems, Inc.

Herman WongRobert Elleman

USEPARegion 10


Overview

• Background

• Guidance development process

• Contents

• Completion of the document


Background

• EPA meteorological guidance documents– 2000 Meteorological Monitoring Guidance for

Regulatory Modeling Applications • Updating the “On-Site Guidance”

– 2008 Quality Assurance Handbook for Air Pollution Measurement Systems, Volume IV: Meteorological Measurements

• Provided updates to work performed by Lockhart and others detailing QA fundamentals and procedures

• Need for additional remote sensing instrumentation guidance


Instrumentation

• Profiling radiometers– Passive measurement technique

– Continuous measurement profiles

– Temperature, humidity and liquid water profiles


Guidance Development Process

1. Develop a first draft document based on principles in the existing documents

2. Implement the draft guidance in a real-world application

3. Observe the measurement and QAPP development process

4. Observe the implementation of the guidance measurement and QA process

5. Modify the guidance based on the observations

6. Obtain a peer review of the final draft document

7. Finalize the guidance document


Document Contents

1. Fundamentals

2. Performance Characteristics

3. Monitoring Goals and Objectives

4. Siting and Exposure

5. Installation and Acceptance Testing

6. Quality Assurance and Quality Control

7. Data Processing and Management

8. Recommendations for Data Collection

9. References


Document Contents

1. Fundamentals

2. Performance Characteristics

3. Monitoring Goals and Objectives

4. Siting and Exposure

5. Installation and Acceptance Testing

6. Quality Assurance and Quality Control

7. Data Processing and Management

8. Recommendations for Data Collection

9. References


Document ContentsFundamentals

• Operation is based on the principle that all matter with a temperature other than absolute zero emits microwave radiation

• The spectrum and intensity is determined by the physical temperature and structure of the matter

• Temperature 50 – 60 GHz Oxygen absorption

• Specific frequency determines the effective volume of the measurement



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Multiple Channel



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Multi-channel

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Multi-channel




Multi-channel




Multi-channel




Multi-channel




Multi-channel




Multi-channel




Multi-channel




Multi-channel




Multi-channel



Quality Assurance and Quality Control

• Calibration methods

• System and performance audits

• Standard operating procedures

• Operational checks and preventive maintenance

• Corrective action and reporting


Quality Assurance and Quality Control

• Calibration methods

• System and performance audits

• Standard operating procedures

• Operational checks and preventive maintenance

• Corrective action and reporting


Performance Audits

• Not amenable to traditional “hands-on” type standards comparison

• Techniques for RASS– Tethered sonde

– Radiosonde


Performance Audits



– Radiosonde


Performance Audits



– Radiosonde


Performance Audits

• Performance evaluation criteria– Quantifiable differences between the two

systems

– Assessment of the detection of significant inflections in the profiles

– Assessment of the accuracy of the reported lapse rates

• Assess the significance of the comparisons not meeting the suggested criteria


Performance Audits


Performance Audits


Summary

• Profiling radiometers provide a continuous measure of temperature profiles

• The resulting data may not match what is obtained from a radiosonde

• Important to understand if the differences are significant

• Assess the value of continuous measurements versus infrequent or derived data from other sources

• Given the above, the document provides guidance for users on the operation, quality assurance, quality control and data validation of information obtained from profiling radiometers


Process Completion









Process Completion









Development of the USEPA Quality Assurance Guidance for the

Collection of Meteorological Data Using Passive Radiometers

Robert A. Baxter, CCMT&B Systems, Inc.

Herman WongRobert Elleman

USEPARegion 10

Development of the USEPA Quality Assurance Guidance for the Collection of Meteorological Data Using Passive Radiometers

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