Dust Radiation, Electrification and Alignment in the Middle East (DREAME)
Lead Research Organisation:
University of Hertfordshire
Department Name: Science and Technology RI
Abstract
Mineral dusts in the atmosphere, originating primarily from dry regions like the Sahara desert, have significant influence on climate. Because of this they need to be accurately represented in climate and weather prediction models. Recent observations of atmospheric Saharan dust by UK scientists provide strong evidence for the existence in mineral dust layers of particles that are predominantly vertically aligned. This alignment is thought to be due to atmospheric electricity associated with the dust layers. Computer modelling indicates that the alignment can significantly change the properties of the dust layers, including the amount of light they transmit, absorb and reflect. This has been termed a 'Venetian blind effect' from the way the tilted particles influence the amount of transmitted light and heat. Change in this and other properties can have significant impact on measurements of dust clouds from satellites, and possibly also on dust movement through the atmosphere. The proposed project will answer urgent questions concerning the precise origin, magnitude, extent and impact of this phenomenon by the use of a variety of measurements from the ground, balloons and aircraft, carried out in the Middle East. The project will result in improved understanding of dust and has the potential to solve a long-standing enigma concerning the movement of dust clouds on the continental scale. The proposal takes advantage of a major opportunity offered by the UK Met Office MEVEX flight campaign, to carry out this project at little additional cost. Therefore it provides excellent value for money.
Publications
Zbigniew Ulanowski (Author)
(2012)
Measurements of atmospheric volcanic ash using an aerosol radiosonde
Nicoll K
(2011)
Observations of Saharan dust layer electrification
in Environmental Research Letters
Ulanowski Z.
(2014)
Profiling of atmospheric volcanic ash layers using an aerosol radiosonde
in InternatIonal Conference on Atmospheric Dust, Book of Abstracts
Zbigniew Ulanowski (Author)
(2012)
Radiosonde aerosol counter for vertical profiling of atmospheric dust layers
Harrison R
(2010)
Self-charging of the Eyjafjallajökull volcanic ash plume
in Environmental Research Letters
Description | We showed that airborne desert dust is electrically charged, to levels that can explain previous observations of the alignment of dust particles in the atmosphere. A byproduct of the project has been an aerosol radiosonde for launching on meteorological balloons. |
Exploitation Route | The radiosondes have already been used for detecting ash from the Eyafjallajokull eruption. The Met Office stocks them for use during future volcanic events. The aerosol radiosondes developed by this project can be used for atmospheric aerosol, including volcanic ash. A project is due to start shortly where a commercial version of the radiosonde will be developed. |
Sectors | Aerospace Defence and Marine Environment Transport |
URL | http://www.herts.ac.uk/research/stri/research-areas/cair/LSRP/atmospheric-dust |
Description | The dust radiosondes developed during the project were used in 2010 and 2011 to verify the presence of volcanic ash from Icelandic volcanoes. The data was then used to justify airspace closure. The sondes are now kept by the Met Office as a contingency measure in case of future eruptions. The radiosondes then led to the development of particle counters that have become the subject of several further development and research projects. These have included installation of measurement systems on two research aircraft in the UK and Germany. |
Sector | Aerospace, Defence and Marine |
Impact Types | Societal |
Title | Low-cost optical particle counters |
Description | The project led to a range of low-cost optical particle counters, the first of which were deployed during DREAME on meteorological balloons, as non-returnable atmospheric aerosol sondes. |
Type Of Material | Improvements to research infrastructure |
Year Produced | 2010 |
Provided To Others? | Yes |
Impact | The optical particle counters were used during the 2010 Eyjafjallajokull volcanic eruption, to show the presence of airborne ash, and thus to verify ash dispersion models. This justified the closure of European airspace. |
URL | https://www.herts.ac.uk/research/centres-and-groups/cacp/particle-instruments-and-diagnostics/low-co... |
Description | Ash sondes |
Organisation | Meteorological Office UK |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | We have provided the Met Office with radiosondes for detecting volcanic ash in the atmosphere. |
Collaborator Contribution | The Met Office paid for constructing the radiosondes and collaborated in testing them. |
Impact | The sondes were used to verify ash dispersion model results during Icelandic volcano eruptions. |
Start Year | 2010 |
Title | Detection of a fluid-borne particle using optical scattering |
Description | Detecting the size and concentration of fluid-borne particles using optical light scattering. A flow of particles 10 passes through laser beam 12 in a scattering chamber. A single reflector or refractor means such as an elliptical or spherical mirror 14 is positioned such that its primary focus 16 lies on the axis of the laser beam 12 in an optically defined particle sensing zone. Scattered light from the particles in the optically defined particle sensing zone is reflected by mirror 14 to photo-detector 24 placed at the secondary focus 20 of the mirror 14. The photo-detector 24 comprises two photosensitive detection areas 26, 28. Means are provided for deriving data from the radiation detected by the first photosensitive detection area 26 and second photosensitive detection area 28 of the detection means. Therefore the elliptical mirror 14 and photo-detector 24 provide a method of optically defining a sensing zone within the illuminating laser beam. |
IP Reference | GB2484930 |
Protection | Patent granted |
Year Protection Granted | 2012 |
Licensed | Yes |
Impact | The AirSensa project is creating a UK-wide network of urban air quality monitors that include OPC-N2 technology. They are starting in Greater London, to monitor and visualise air quality right down to individual street level. Up to 10,000 sensors are to be placed in schools, public and commercial buildings to monitor and feed back data to the cloud where it will be made available online and via smart-phone apps. |