The European Water Framework Directive specifies very low permitted levels for pollutants that present a significant risk to, or via, the aquatic environment. Toxic pollutants such as tributyltin, polybrominated diphenylether and selected polycyclic aromatic hydrocarbons are particularly harmful as they are liable to accumulate in the food chain.

The EMRP project Traceable measurement for monitoring critical pollutants under the European Water Framework Directive (ENV08 WFD) developed validated SI traceable reference methods based on isotope dilution for the analysis of these pollutants in water samples at the low levels required to comply with the Directive. These methods allow the quality of measurements made in public and commercial labs to be validated and they are already being deployed in several European regions.

Monitoring and reducing industrial pollution is essential for preserving our environment. Harmful gases from a variety of industries are contributing to climate change or damaging our health. EMRP research has targeted a number of these emissions resulting in greater monitoring accuracy under real conditions and supporting improved assessments of industrial emission release reduction strategies.

The EMRP research projects developed increased calibration rigor for a variety of reactive pollutant gases, including the ammonia (ENV55 MetNH3) that is released by intensive farming, the fluorocarbons (ENV52 HIGHGAS) released from air conditioning systems and the volatile organic compounds emitted outdoors by the oil and gas industry and indoors from construction products and furnishings (ENV56 KEY-VOCs). EU Directives regulate these emissions and require users to robustly demonstrate compliance as emission limits tighten.

To address pollution from industrial plants, the EMRP project Metrology to underpin future regulation of industrial emissions (ENV60 IMPRESS) developed facilities which mimic stack discharges. These were used to compare the performance of optically based monitoring techniques against methods authorised for regulatory compliance. Evaluation of test methods under near site conditions enabled in-the-field measurement protocols to be determined. A revised CEN standard now incorporates these protocols – a first step towards their implementation in industrial plant and use for demonstrating EU Directive compliance.

To meet the demands for greater accuracy in earth observation measurements that are made by satellite borne instrumentation new high altitude and ground based confirmatory measurements, with rigorous SI traceability, are required.

The EMRP project European metrology for Earth observation and climate (ENV04 MetEOC) developed methods to confirm the performance of orbiting instrumentation using transfer standards and a spectroradiometer which are carried high into the atmosphere on an aircraft. This has increased the measurement accuracy of satellite-borne instruments by a factor of 10.

In addition, research in the EMRP project European metrology for Earth observation and climate as enabled the accurate characterisation of two new desert test-sites for use in confirming the performance of satellite-based radiance instrumentation. This is supporting the Committee on Earth Observation Satellites (CEOS) RadCalNet network, whilst careful radiance measurements of leaf reflections at Wytham Woods in the UK have resulted in its designation as a CEOS super-site. In addition, EMRP research developed traceable protocols for calibrating satellite borne ocean surface radiance instrumentation. This is a key measurement parameter for detecting climate change trends based on measuring the colour of phytoplankton blooms.

Detecting trends in the weather, as global warming creates more severe storms and droughts, relies on accurately monitoring key parameters such as temperature and humidity using land-, sea- and air-based instrumentation. Automatic weather stations provide data for short-term weather prediction, with increased accuracy these could significantly increase data availability for climate trend determination. The EMRP project Metrology for essential climate variables (ENV58 MeteoMet2) introduced improved links to the SI units for the calibration of sensors used to detect temperature changes deep in the ocean and for those used high in the atmosphere to monitor humidity.

This EURAMET funded research has also improved the accuracy of the temperature data generated by automated weather stations, thus making it more suitable for use by climatologists when predicting global warming trends.

Improving air quality requires accurate measurements of pollutants at the low concentrations which are permitted by European regulation. The EMRP project Metrology for chemical pollutants in air (ENV01 MACPoll) developed preparation methods for the following calibration gases SO₂, NO and NO₂ at or near the limit values specified in the regulations. A practical portable NO₂ generator was also developed for the cost- effective calibration of air quality sensors in the field.

The NO₂ generator has been used by the City of Zürich Health and Environment Department to calibrate its installed air quality sensors, enabling it to evaluate its pollution reduction strategy and maintain its lead in reducing city centre pollution.