Download - Unstable Science Question 2
Unstable Science Question 2
John HanesiakCEOS, U. Manitoba
Unstable Workshop, Edmonton, ABApril 18-19, 2007
Science Question 2
• What are the contributions of surface processes to the initiation of deep moist convection and the development of severe thunderstorms in the Alberta Foothills region?
Equipment• Radiometrics WVR-1100
– Total column vapor and liquid water– Temporal resolution depends on scanning cycle
• Acoustic Doppler sodar– 3-component winds & standard deviations– Up to 1km, 50m resolution, 15-30 min averages
• AERI– Vertical profiles of temperature & vapor– Up to 3km, 100-200m resolution, every 15 min– Limitation = clouds & low level saturation
• Radiometrics 3000A– Vertical profiles of temperature & vapor, cloud base, & total column– Up to 10km, 100-250m resolution, less than 5 min– Limitation = precipitation
• MARS (Mobile Atmospheric Research System)• Portable rawinsonde• 2 Campbell Sci weather stations• Laser precipitation sensor• Mobile vehicle (T, RH, wind)
• Mobile Atmospheric Research System (MARS)• UofM URGP & NSERC
sodar AERI AMR
weatherstation
portable rawinsonde
Sub-Questions & Methods• (a) Is there a noticeable difference in storm initiation and evolution between wet
and dry areas over the cropped region (as defined by a crop model) over the duration of the project?
• (b) Are there noticeable gradients of surface and boundary layer water vapour across the major wet/dry areas and how do these evolve over the project?
• J. Brimelow
Sub-Questions & Methods• (c) Are mesoscale circulations detectable in the vicinity of boundaries
between wet and dry areas? If so, how do they appear to influence storm initiation and evolution?
Methods:• Mobile observations (surface vehicle & sodar on MARS)• Mesonet• Array of rawinsondes• Aircraft• Radar?• Satellite & radar for initiation zones in association with these
observations
Sub-Questions & Methods• (d) What are the latent and sensible heat fluxes over the region,
especially across any wet/dry areas that may exist? How do they influence temperature and water vapor stratification?
Methods:• Aircraft• Any available eddy correlation or bulk profile measurements• Rawinsondes, MARS, radiometers, boundary layer models
Sub-Questions & Methods• (e) How does the orientation of synoptic (background) flows modify
(b) - (d) on a day-to-day basis?
Methods:• Synoptic analysis fields in relation to field measurements (i.e. are
there detectable spatial 3D variations in thermodynamic and dynamic fields … transient boundaries)
• Perpendicular versus angled synoptic flows in relation to surface wet/dry boundaries
Sub-Questions & Methods• (f) Can the surface contributions to total boundary layer moisture be
quantified?
Methods:• Aircraft flux measurements• Water balance exercise• Estimated as a residual in the water balance equations?• How do we deal with storage?
Sub-Questions & Methods• (g) How can the existing observational network be improved to better
represent surface processes that contribute to the initiation and development of severe thunderstorms?
Methods:• Soil moisture / flux measurement sensor array (strategic areas)• Make better use of satellite surface products (validation)• “enhance” confidence in crop model and/or CLASS output
Break-Outs
• Refinement of the UNSTABLE science questions• Data, instrumentation and deployment strategies
necessary to answer the science questions• Who plans to be directly involved in the
UNSTABLE field campaign and how• Funding strategies and opportunities for in-kind
support• Others as suggested by discussion groups