lightning-produced nitrogen oxides during active: what have we learned thus far?
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Lightning-Produced Nitrogen Oxides during ACTIVE: what have we learned thus far?. Lorenzo Labrador, Geraint Vaughan and the ACTIVE team ([email protected]) SEAES, University of Manchester. LINET stroke time series, ACTIVE campaign. Total ic cg. - PowerPoint PPT PresentationTRANSCRIPT
Lightning-Produced Nitrogen Oxides during ACTIVE: what have we learned
thus far?
Lorenzo Labrador, Geraint Vaughan and the ACTIVE team([email protected])
SEAES, University of Manchester.
LINET stroke time series, ACTIVE campaign
Total
ic
cgMini-monsoon
Pre-monsoon
Monsoon
Mo
ns
oo
n-b
rea
k
Suppressed monsoon
MCS
Lightning-produced NOx in Hector storms, pre-monsoon
16/11/2005 Egrett’s flight track, LINET lightning strokes
Average in-cloud NOx enhancement value = 2.5 ppbv
16/11/2005 Egrett’s altitude profile, NOx, CO and cloud particles
LINET- detected strokes in storm ≥ 10KA = 832 (24.5% of storm’s total)
Lightning-produced NOx in Hector storms, monsoon break
16/11/2005 Egrett’s flight track, LINET lightning strokes
Average in-cloud NOx enhancement value = 1.16 ppbv
10/02/2002 AE27 Egrett’s altitude profile, NOx, CO and cloud particles
LINET- detected strokes in storm ≥ 10KA = 1188(20.9% of storm’s total)
Lightning-NOx production
Fltnox = Χltnox M(N)/M(air) ρair (va – vs) Δx Δz
Pltnox = Fltnox/RLINET (RLINET/RLIS)-> Pltnox= Fltnox/RLIS ;
GLtNOx = Pltnox x Global flash rate
AE04 = Pltnox= Fltnox/RLIS = 1.69 kg(NO) flash-1
AE04 GLtNOx = 2.34 Tg yr-1
AE27 = Pltnox= Fltnox/RLIS = 0.234 kg(NO) flash-1
AE27 GLtNOx = 0.32 Tg yr-1
Lightning-produced NOx in monsoon convection
22/01/2005 Egrett’s flight track, LINET lightning strokes, 00:00-23:59 UTC22/01/2005 Egrett’s altitude profile, NOx,
CO and cloud particles
Average in-cloud NOx enhancement value = 984 ppt
Storm sampled produced only 9 lightning strokes and only 17% of that day’s strokes had been produced by the time the flight ended. So, where did the NOx in the spikes come from?
22/01/2005 Egrett’s flight track, LINET lightning strokes, 00:00-10:00 UTC (end of flight)
Average out-of-cloud NOx enhancement value =720 ppt
AE18’s 3rd NOx spike (741 pptv NOx)
AE18’s 7th NOx spike (1570 pptv NOx)
5-day backward-trajectories suggest that airmass sampled may have accrued NOx during transit over convectively-active region
22/01/06; flight AE18’s 5-day backward trajectories
Conclusions
• The tropics play a crucial role in the production and redistribution of Lightning-produced NOx
• LtNOx production in Hector storms on a par with tropical continental convection elsewhere (Brazil), although further studies are warranted
• Lightning-NOX in monsoon convection more significant than previously thought
NO: Vertical profiles
Conclussions