BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Laser tomography for wide area gas emission spatio-temporal recons
 truction - Dr Damien Weidmann\, Space Science & Technology Dept (RAL Space
 )
DTSTART:20260514T100000Z
DTEND:20260514T110000Z
UID:TALK246571@talks.cam.ac.uk
CONTACT:Yao Ge
DESCRIPTION:Abstract: \nThrough injection of gas phase chemicals such as g
 reenhouse gases (GHGs) and pollutants\, the composition of the Earth's atm
 osphere is changing\, affecting radiative\, chemical\, and transport proce
 sses within the atmosphere\, and the health of bio-receptors and ecosystem
 s. Understanding natural and anthropogenic processes leading to gas emissi
 ons requires quantitative observations at the scale of the emitting unit\,
  with a temporal and spatial resolutions allowing to resolve dynamic emiss
 ion behaviours and their spatial patterns. In the case of anthropogenic GH
 G emissions from the energy\, the waste management\, or the agricultural s
 ectors\, spatio-temporal quantification of gas emitted at the facility sca
 le is also critical to the implementation of sustainable climate policies\
 , such as the Net Zero agenda\, to allow for fair and transparent reportin
 g\, monitoring and verification.\nConsidering methane\, great progress has
  been made towards improved quantitative emission monitoring to reconcile 
 bottom-up emission inventories and top-down estimates. Novel measurement s
 ystems\, particularly satellite-borne ones\, now provides global coverage 
 when the cloud cover allows\, and can 'focus' on large facilities to provi
 de snapshot quantitative estimates. However\, this way only fairly large e
 missions can be measured (~100kg/h)\, and a snapshot measurement does not 
 provide the temporal patterns of emissions often associated to facility op
 erations. Satellite-borne measurements also need robust ground-based valid
 ation to demonstrate their data quality.\n\nIn this context\, the need for
  continuous gas emission monitoring systems capable of characterising the 
 emitting behaviour of an entire facility\, in space and time\, remains acu
 te. To address the need\, we have developed the concept of gas emission la
 ser tomography made of 1) high-resolution spectroscopic measurements of at
 mospheric transmission over multiple open-paths\, and 2) a inversion schem
 e to reconstruct\, from the time series of multi-path integrated concentra
 tions\, the evolution of three dimensional gas plumes and associated emiss
 ion sources.\nField deployments at oil and gas\, waste treatment\, and agr
 icultural facilities\, together with controlled gas released tests\, have 
 established the highly promising capabilities of gas emission laser tomogr
 aphy for methane characterisation. We will describe the system\, present s
 ome example of deployments and results\, and discuss the current developme
 nts to additional trace gases\, as well as improvements of the inversion f
 ramework based on Bayesian state estimation.\n\nBiography: \nDamien Weidma
 nn heads the Spectroscopy programme of the Space Science and Technology De
 partment of the STFC Rutherford Appleton Laboratory (aka RAL Space). He ha
 s been conducting research and development for more than 30 years in molec
 ular spectroscopy and atmospheric sensing\, in France\, the USA and the UK
 . He has a particular interest in the development and application of novel
  high resolution chemical sensing concepts enabled by spectroscopy\, cover
 ing technologies\, algorithms\, systems\, and mission concepts. DW is also
  co-founder and chief scientific officer of MIRICO Ltd\, a company exploit
 ing high-precision gas sensing for terrestrial applications.
LOCATION:Chemistry Dept\, Unilever Lecture Theatre and Teams
END:VEVENT
END:VCALENDAR