2.4 Some observations from the JET2000 experiment

 

Thorncroft et al, 2003 BAMS

Parker et al, 2005 QJRMS

• C130 aircraft flew 4 legs over this region: 25-30 August 2000

• Dropsondes every 0.5-1 degree

• Low level flights on north-south transect

Met Office C-130At Niamey Airport, Niger

Experimental Details

JET2000 Period

Weak AEW activity

2-5 day filtered V at 700mb (from ECMWF)

Dropsonde locations – on the 28th August 2000

ECMWF PBL fields compared to observations

Potential temperature

Equivalent potential temperature

Zonal Wind 28th August 2000

Thermodynamic Profiles 28th August 2000

Thermodynamic Profiles 28th August 2000

Thermodynamic Profiles 28th August 2000

Height of AEJ

Saturated equivalent potential temperature 28th August 2000

Close to dry adiabatic

Closer to moist adiabatic

Equivalent Potential Temperature 28th August 2000

Elevated SAL is a region of lateral mixing (e.g. q, aerosol)

Variability in boundary layer θe (surface conditions)

Boundary Layer Buoyancy 28th August 2000

Larger CIN and +ve buoyancy

Smaller CIN and +ve buoyancy