The Arctic Turbulence Experiment 2006, Direct measurements of turbulent fluxes in the near surface environment at high latitudes applying the eddy-covariance method, Part 2

UNIVERSITY o BAYREUTH Depa men o Mic ome eo ology The A c ic Tu bulence Expe imen 2006 Di ec measu emen s o u bulen luxes in he nea su ace en i onmen a high la i udes applying he eddy-co a iance me hod PART 2 Nea su ace measu emen s du ing he ARCTEX 2006 campaign May, 2nd o May, 20 h 2006 Johannes Lüe s and Jö g Ba eiss Wo k Repo No. 32 Bay eu h, Augus 2007 2 Con en s 1 In oduc ion.......................................................................................................... 3 2 Gene al In o ma ion............................................................................................. 4 2.1 Loca ion........................................................................................................ 4 2.2 Su ace and wea he condi ions................................................................... 5 3 O e iew o measu emen si es.......................................................................... 6 4 Visualiza ion o s anda d me eo ological measu emen s.................................... 7 4.1 Synop ic si ua ion......................................................................................... 7 4.2 En i e obse a ion pe iod ........................................................................... 20 4.3 Daily cha s ................................................................................................ 27 5 Visualiza ion o di ec ly measu ed u bulence luxes......................................... 59 5.1 Calcula ion o u bulen luxes wi h he so wa e package TK2.................. 59 5.2 En i e obse a ion pe iod ........................................................................... 60 5.3 Daily cha s ................................................................................................ 69 6 Da a a chi ed a Ny-Ålesund (CDs) .................................................................. 74 3 1 In oduc ion Abs ac Accu a e quan i ica ion o u bulen luxes be ween he su ace and he a mosphe ic bounda y laye in pola en i onmen s, cha ac e ized by equen s able o e y s able s a i ied condi ions, is a undamen al p oblem in soil-snow-ice- ege a ion-a mosphe e in e ac ion s udies. The obse ed apid clima e wa ming in he A c ic equi es imp o emen s in he moni o ing o ene gy and ma e exchange; accomplished by se ing up app op ia e (adap ed o pola condi ions) obse a ion si es o measu e u bulen luxes. To add ess hese p oblems, i is essen ial o imp o e he da abases wi h high-quali y in-si u measu emen s o u bulen luxes nea he su ace applying he Eddy- Co a iance me hod. These di ec measu emen da a (CSAT3 sonic anemome e , KH20 k yp on hyg ome e , and lase scin illome e ) ob ained du ing he i s A c ic Tu bulence Expe imen (ARCTEX-2006) in May 2006 a he F ench-Ge man A c ic Resea ch Base in Ny-Ålesund (AWI/IPEV) on Spi sbe gen (S alba d) allowed a compa ison wi h simula ed esul s om simple lux g adien - pa ame e iza ions used oday o o ce a mosphe e-ocean-ice models. In addi ion, he esul s o his pilo s udy shows he p oblem o di ec measu emen s (e.g. snow d i h ough he senso pa h ways) unde ough wea he condi ions as well as hey e eal ha he mises ima ing o sensible hea luxes can esul om inaccu a e measu emen s o calcula ion o he su ace empe a u e and inapp op ia e ea men o he neu al and s able condi ions (e.g. in e mi ency, g a i y wa es) in he bulk pa ame e iza ion. The p ima y goals o he ARCTEX-campaign we e: 1. con inuous measu emen s o high- esolu ion (20 Hz) u bulen hea luxes nea he und a su ace using a ul a sonic anemome e (eddy-co a iance me hod) and an ul a iole k yp on hyg ome e , 2. con inuous measu emen s o he u bulen sensible hea lux nea he und a su ace using he Lase -scin illome y, 3. measu emen s o s anda d me eo ological da a sampled a 1s in e als using a me eo ological g adien owe (6 m and 10 m), 4. p e- and pos - p ocessing o high-quali y da a se s o u bulen luxes using s a e o he a lux da a quali y assessmen echniques, 5. unde s anding o exchange p ocesses and hei pa ame e iza ion o neu al and s able condi ions, 6. alida ion o commonly used sensible and la en hea lux pa ame e iza ions (ae odynamic app oach, bulk and g adien me hod). 4 2 Gene al In o ma ion 2.1 Loca ion De ailed geog aphic loca ions o he “A c ic Tu bulence Expe imen 2006” (ARCTEX-2006) a Ny- Ålesund (S alba d, Kongs jo den), May 2006, Uni e si ies o Bay eu h and T ie , Ge many: Gene al loca ion S alba d, Kongs jo den, Ny- Ålesund, Posi ion (Cen e o se lemen ): 078° 55’ 24’’ N, 011° 55’ 15’’ E Eddy-Flux complex UBT (EF): Coo dina es: 078° 55’ 02’’ N, 011° 55’ 52’’ E Al i ude: 13 m a. s. l. Land use: snow co e ed und a Me eo ological owe AWI (MT1): Coo dina es: 078° 55’ 04’’ N, 011° 55’ 26’’ E Al i ude: 14 m a. s. l. Land use: snow co e ed und a Me eo ological owe UBT (MT2): Coo dina es: 078° 55’ 03’’ N, 011° 55’ 34’’ E Al i ude: 14 m a. s. l. Land use: snow co e ed und a Scin illome e UBT (SLS): Coo dina es: 078° 55’ 00’’ N, 011° 56’ 00’’ E Al i ude: 13.5 m a. s. l. Land use: snow co e ed und a Te he ed balloon AWI (TB1): Coo dina es: 078° 55’ 06’’ N, 011° 55’ 23’’ E Al i ude: 11 m a. s. l. Land use: snow co e ed und a Te he ed balloon AWI (TB2): Coo dina es: 078° 55’ 27’’ N, 011° 56’ 07’’ E Al i ude: 3 m a. s. l. Land use: Ha bo (conc e e), jo d (wa e ) Radiosonde AWI (RS): Coo dina es: 078° 55’ 06’’ N, 011° 55’ 23’’ E Al i ude: 11 m a. s. l. Land use: snow co e ed und a BSRN AWI (BSRN): Coo dina es: 078° 56’ 05’’ N, 011° 56’ E Al i ude: 11 m a. s. l. Land use: snow co e ed und a Time zone Cen al Eu opean Time: CET = GMT + 1 h (win e ) CEST = GMT + 2 h (summe ). Gi en imes and ilenames e lec s a ing ime o in e als UBT=Uni . o Bay eu h; AWI= Al ed Wegene Ins i u e o Pola - and Ma ine Resea ch; BSRN= Baseline Su ace Radia ion Ne wo k 5 2.2 Su ace and wea he condi ions Table 2.1 lis s he su ace and wea he condi ions du ing he ARCTEX-2006 campaign. No ewo hy, is he ex eme wa m pe iod un il e ening May 7 and he hea y snow-s o m a nigh , May 7 o May 8. Table 2.1: Su ace and wea he condi ions du ing he ARCTEX-2006 campaign. May 3 o May 5 we mel ing snow o e ice, la ge snow ee spo s (ba e soil, und a), su ace mel wa e , some ain all and pa ly cloudy, A c ic Haze e en , ex emely wa m, empe a u e ange: +3 °C o +8 °C May 6 o May 8 1s s o m and hea y snow all, hea y snowd i ; o e cas wea he , ex emely wa m (+8 °C) un il beginning o he 2nd s o m on May 7, 19 h CET and empe a u e d op o mo e han 16 K (−10 °C) May 9 o May 11 esh snow co e , p edominan ly sunny wea he , empe a u e ange: − 5 °C o −2 °C May 12 o May 14 ongoing snowd i , snow co e deple ing, a 13 h pm empe a u e a ound 0 °C, p edominan ly o e cas o pa ly cloudy wea he , empe a u e ange: −4 °C o 0 °C May 15 o May 16 ongoing snowd i , some snow ee spo s, a g ound e ozen and compac ed hin ice laye s, p edominan ly sunny o pa ly cloudy wea he , empe a u e ange: −4 °C o −1 °C May 17 o May 19 mel ing snow o e ice, some snow ee spo s (ba e soil, und a), ligh o mode a e ain and/o snow all (17 h and 18 h, empe a u e ange: −2 °C o +1 °C) 6 3 O e iew o measu emen si es The map (Figu e 3.1) o Ny-Ålesund (S alba d) shows he measu emen si es du ing he ARCTEX-2006 campaign. The pe manen AWI/IPEV si es used o his s udy a e he 10 m me eo ological owe o he Al ed Wegene Ins i u e o Pola and Ma ine Resea ch (MT1), he in e na ional s anda dized adia ion measu emen s o he Baseline Su ace Radia ion Ne wo k (BSRN), he WMO 1004 adiosonde launch si e (RS) and he empo a y AWI e he ed balloon launch si es TB1 and TB2. The empo a y si es - build up by he Uni e si ies o Bay eu h and T ie - a e he 6 m me eo ological owe (MT2), he eddy- lux measu emen complex wi h sonic anemome e (EF), and he Lase -scin illome e pa hway (SLS). TB2 RS TB1 MT1 MT2 EF SLS BSRN Eddy-Flux Complex UBT Me eo ological G adien Towe UBT Scin illome e UBT Figu e 3.1: Map o Ny-Ålesund (S alba d, Kongs jo den) showing he measu emen si es du ing he ARCTEX-2006 campaign: MT1 (10 m me eo ological owe o he Al ed Wegene Ins i u e o Pola and Ma ine Resea ch), MT2 (6 m me eo ological owe o he Uni e si y o Bay eu h), EF (eddy- lux measu emen complex), SLS (si e o scin illome e measu emen s), BSRN ( adia ion measu emen s o he Baseline Su ace Radia ion Measu emen s), RS ( adiosonde launch si e), TB1 and TB2 ( e he ed balloon launch si es). The base map was kindly p o ided by he No wegian Pola Ins i u e. 7 4 Visualiza ion o s anda d me eo ological measu emen s 4.1 Synop ic si ua ion Ope a ional Su ace Analysis Cha s o he Me eo ological Se ice o Canada, Wea he o ice (www.wea he o ice.gc.ca), comple e No he n Hemisphe ic co e age. The ollowing cha s o he Global En i onmen al Mul iscale Model (GEM) ou line he synop ic si ua ion be ween May 5 and May 18, 2006. Rema kable was he passage o an a c ic cyclone on May 7 and May 8, 2006 ac oss Spi sbe gen causing hea y snow all and wind speeds up o mo e han 80 km/h. 8 9 16 17 18 19 20 4.2 En i e obse a ion pe iod Tempe a u e Du ing he ARCTEX-2006 campaign he empe a u e d ops om +8 °C o −9 °C du ing he passage o a cold on o an a c ic s o m cyclone in he nigh o May 7 o May 8, 2006 (Figu e 4.1). A e wa ds, un il he mo ning o May 12, a pe iod o sunny, clea sky wea he occu s esul ing in a s ong posi i e empe a u e g adien ( empe a u e in e sion) and ex eme s abile s a i ica ion in be ween he i s 10 m abo e he snow co e in he h ee “nigh s” May 9 o May 12 (compa e Figu e 4.1 and Figu e 4.2.). Only a ound noon o May 13, May 14 and May 16 a ligh nega i e empe a u e g adien accompanied by a b eakdown o he wind sys em occu s each ime jus o ew hou s esul ing in a weak posi i e hea lux. Figu e 4.1: Ai empe a u e May 5 o May 19, 2006. Black do s: ai empe a u e in °C a 0.7 m a. g. l. (g adien owe MT2, Uni . o Bay eu h). G ey do s: ai empe a u e in °C a 10.0 m a. g. l. (me eo . owe MT1, Al ed Wegene Ins i u e o Pola and Ma ine Resea ch). Ny-Ålesund (S alba d), ARCTEX-2006 campaign. Figu e 4.2: Ve ical di e ence o ai empe a u e and wind speed May 5 o May 19, 2006. Black do s: ∆T di e ence o ai empe a u e in K be ween 10 m and 0.7 m a. g. l. G ey do s: ∆u di e ence o wind speed in m s−1 be ween 10.0 m and 0.7 m a. g. l. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. 21 Humidi y The low le el o he absolu e humidi y amoun a ound 2 o 3 g m−3 is ypical o a cold a c ic ai mass. Only unde in luence o he wa m ai mass sec o o he passing cyclone he wa e apo amoun inc eases signi ican bu eaching sa u a ion only du ing he hea y snow s o m a May 7 (Figu e 4.3). Figu e 4.3: Humidi y May 5 o May 19, 2006. Black do s: ela i e humidi y in % a 1.5 m a. g. l. G ey do s: absolu e humidi y in g m−3 a 10.0 m a. g. l. (bo h me eo . owe MT1, Al ed Wegene Ins i u e o Pola and Ma ine Resea ch). Ny-Ålesund (S alba d), ARCTEX-2006 campaign. Wind speed and wind di ec ion The ho izon al wind speed a di e en heigh s abo e g ound le el (0.7 m up o 10 m) was ob ained by he g adien owe o he Uni e si y o Bay eu h (MT2) using he Clima onics F460 cup anemome e s as well by he ou ine obse a ion o he me eo ological owe o he Al ed Wegene Ins i u e o Pola and Ma ine Resea ch (MT1). Figu e 4.4: Wind speed May 5 o May 19, 2006. Black do s: wind speed in m s−1 a 0.7 m a. g. l. (g adien owe MT2, Uni . o Bay eu h). G ey do s: wind speed in m s−1 a 10.0 m a. g. l. (me eo . owe MT1, Al ed Wegene Ins i u e o Pola and Ma ine Resea ch). Ny-Ålesund (S alba d), ARCTEX-2006 campaign. 22 The Figu e 4.4 indica es ha a mos o he ime he usual e ical wind p o ile domina es. Du ing ew pe iods be ween May 7 and May 12 (esp. du ing he clea sky days) he nea su ace wind speed ( i s 3 m) exceeds he speeds a 10 m a. g. l. (compa e Figu e 4.2). A close look e eals a mo e o less 2 m o 3 m hick ai low coming om sou h-wes downhill he slope om he nea Zeppelin Moun ain Range. Figu e 4.5: Wind di ec ion and wind speed May 5 o May 19, 2006. Black do s: wind speed in m s−1 a 10.0 m a. g. l. G ey do s: wind di ec ion in deg ee a 10.0 m a. g. l. (bo h me eo . owe MT1, Al ed Wegene Ins i u e o Pola and Ma ine Resea ch). The small ba s a he plo ’s op boa de indica e signi ican change o he wind egime (namely SE and NW) o a ansi ion phase. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. The Figu e 4.5 compa es wind speed and he co esponding di ec ion. Be ween May 8 and May 12 he p e ailing wind di ec ion is no h-wes (upwa ds he jo d) in e up ed a midday May 9 by indi e en di ec ions and ela i ely calm wind condi ions and du ing May 11 by change o a s ong sou h-eas ai low. Beginning a ound midnigh May 12 un il noon May 16 he p e ailing di ec ion emains sou h-eas (downwa d he Kongs jo d). A a e noon May 16 a ela i ely wa m and humid ai mass a i ed in Ny-Ålesund due o a low p essu e sys em ac oss he Ba en s Sea. The wind di ec ion (a 2 m and 10 m a. g. l.) was ob ained by he me eo ological ou ine obse a ion o he 10 m all me eo ological owe o he Al ed Wegene Ins i u e o Pola and Ma ine Resea ch (MT1). The used wind senso is a combined anemome e and wind ane (Thies Clima, Ge mamy). The Figu e 4.6 illus a es he bo h main wind di ec ion sec o s a Ny- Ålesund du ing he ARCTEX-2006 campaign. This pa e n o ei he sou h-eas o no h-wes di ec ions (mo e o less canalized ai low down o upwa d he Kongs jo d) is ypical no only in May bu also mos o he ime du ing he yea . A 2 m and du ing weak wind an o sho e sou h-wes componen is dis inguishable (compa e Chap e 4.3: daily wind ose plo s). 23 Figu e 4.6: F equency dis ibu ion o wind di ec ion sepa a ed in 12 wind sec o s and classi ied in 4 wind speed classes, May 1 o May 18, 2006. Abo e: dis ibu ion o he wind di ec ions in deg ee measu ed a 2.0 m heigh a. g. l. Below: dis ibu ion o he wind di ec ion in deg ee measu ed a 10.0 m a. g. l. (bo h me eo . owe MT1, Al ed Wegene Ins i u e o Pola and Ma ine Resea ch). Ny-Ålesund (S alba d), ARCTEX-2006 campaign. 24 Radia ion The adia ion measu emen s ook place a he ou ine BSRN-S a ion (AWI) and a he ARCTEX- 2006 measu emen ield nex o he g adien owe o he Uni . o Bay eu h (MT2). A he la e si e he adia ion measu emen equipmen was especially build-up o e an adequa e hick snow ield. A he BSRN si e a pa e n o mo e o less snow co e ed o snow ee und a a ound he ins umen ield yields o a sligh ly educed amoun o e lec ed sho wa e adia ion in compa ison o he MT2 si e whe eas he global adia ion ecei ed a bo h si es a e ema kable simila (compa e Figu e 4.7 and Figu e 4.8). Figu e 4.7: Global sho wa e adia ion May 5 o May 19, 2006. Black do s: global adia ion in W m−2 measu ed wi h a CM11 (Kipp & Zonen) py anome e (BSRN s a ion, Al ed Wegene Ins i u e o Pola and Ma ine Resea ch). G ey do s: global adia ion in W m−2 measu ed wi h a CNR1 (Kipp & Zonen) ne adiome e (ne adia ion s a ion Uni . o Bay eu h). Ny-Ålesund (S alba d), ARCTEX-2006 campaign. Figu e 4.8: Re lec ed sho wa e adia ion May 5 o May 19, 2006. Black do s: e lec ed adia ion in W m−2 measu ed wi h a CM11 (Kipp & Zonen) py anome e (BSRN s a ion, Al ed Wegene Ins i u e o Pola and Ma ine Resea ch). G ey do s: e lec ed adia ion in W m−2 measu ed wi h a CNR1 (Kipp & Zonen) ne adiome e (ne adia ion s a ion Uni . o Bay eu h). Ny-Ålesund (S alba d), ARCTEX-2006 campaign. 25 Figu e 4.9: Ra io o e lec ed (only alues abo e o equal 10 W m−2) o global sho wa e adia ion (albedo) measu ed wi h a CNR1 (Kipp & Zonen) ne adiome e (ne adia ion s a ion Uni . o Bay eu h) May 5 o May 19, 2006. Ci cles show he daily a iance o he Albedo due o di e en ele a ion angles o he sun and due o di e en ac ion o he hal space om wi ch di use sky adia ion o he - om he su ace - e lec ed adia ion can each he senso s. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. The in e p e a ion o he albedo in pola egions especially du ing snow all o snow mel seasons is di icul . The Figu e 4.9 demons a es his p oblem. Du ing snow all e en s like be ween May 6 and May 7, he albedo changed apidly co e ing a mo e o less snow ee su ace wi h esh snow. A imes wi h clea sky wea he and lowe a e o di use adia ion and a new esh and closed snow co e like om May 8 o May 10 he albedo a ies in a la ge ange depending on he ele a ion angle and he supe imposed e ec o addi ional e lec ed adia ion ecei ing he senso caused by he e lec ion o he su ounding snow co e ed ea h su ace acco ding o he local limi a ion o ex ension o he ho izon. O he wise, a days wi h dec easing snow co e and a highe a e o di use adia ion like May 12 o May 14 o May 17 he daily a ia ion o he albedo is ela i ely small. Figu e 4.10: Longwa e adia ion measu ed wi h a PIR (P ecision In a ed Radiome e , Eppley) Py geome e (BSRN s a ion, Al ed Wegene Ins i u e o Pola and Ma ine Resea ch) May 5 o May 19, 2006. Black do s: incoming long wa e adia ion in W m−2.G ey do s: ou going long wa e adia ion in W m−2. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. 32 Wind speed The wind speed was eco ded in di e en heigh s abo e g ound using cup anemome e s. Mos o he ime he a ea a ound he g adien owe o he Uni e si y o Bay eu h (MT2, measu ing heigh s 0.7 m, 1.4m, 2.4 m and 3.9 m) and a ound he me eo ological owe o he Al ed Wegene Ins i u e o Pola and Ma ine Resea ch (MT1, 10 m) was co e ed by 20 cm o 30 cm snow. The eco ds o he cup anemome e moun ed a 5.6 m had o be neglec ed because o a damage o he ball bea ing a e he s o m e en May 7, May 8. 33 34 35 36 37 Wind di ec ion The wind di ec ion was eco ded wi h a wind ane a he me eo ological owe o he Al ed Wegene Ins i u e o Pola and Ma ine Resea ch Ny-Ålesund (MT1) in 2 m and 10 m abo e he g ound nea by he g adien owe and he eddy lux complex o he Uni e si y o Bay eu h. The gene al calm limi was se o < 0.3 m s−1. A mos o he days be ween May 1 and May 18 he pe cen age o clam e en s a e below 1 % o all measu emen s pe day. The wind ose plo s a e a combina ion o wind speed and ela ed di ec ion o succinc ly show he daily dis ibu ion o equency o pa icula di ec ions sepa a ed in 12 sec o s. The chosen wind speed class limi s a e >= 0.3 o 1.6, > 1.6 o 3.4, > 3.4 o 8.0 and > 8.0 m s−1. No iceable a e he o sho e sou h-wes componen s du ing weak wind especially a May 9 and May 11. 38 39 40 41 48 49 Longwa e adia ion The p esen ed eco dings o he e es ial adia ion and he cloud base heigh a e ob ained by he in e na ional s anda dized adia ion measu emen s o he Baseline Su ace Radia ion Ne wo k (BSRN) and he lase ceilome e (cloud base heigh ) bo h main ained by he Al ed Wegene Ins i u e o Pola and Ma ine Resea ch. The plo s show he incoming and ou going luxes in he longwa e spec al ange and he acco ding cloud heigh . 50 51 52 53 54 Cloud Base heigh in me e 55 56 57 64 Ny-Alesund 0 1 2 3 4 5 6 7 8 9 10 Time [Day] u∗ s eady s a e quali y lag 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 07 08 09 10 11 12 13 14 15 16 17 18 19 20 May 2006 u∗ [m s−1] s a lag_us a ic ion eloci y Figu e 5.9: F ic ion eloci y u∗ (a 2.4 m abo e g ound) ob ained by he eddy co a iance complex EF and he ela ed quali y lags o he S eady S a e es (Foken & Wichu a, 1996; TK2-so wa e) o he co a iance o he luc ua ions o he ho izon al (u', ') and e ical (w') wind componen s (s a lag_us a ). The classes 1 o 3 a e good quali y, he classes 4 o 6 a e usable quali y, class 7 and 8 a e only o o ien a ion, 9 has o be neglec ed, May 7 o May 19, 2006. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. Ny-Alesund 0 1 2 3 4 5 6 7 8 9 10 07 08 09 10 11 12 13 14 15 16 17 18 19 20 Time [Day] QHB s eady s a e quali y lag -40 -30 -20 -10 0 10 20 30 40 May 2006 QHB [W m−2] buoyancy lux s a lag_wTs Figu e 5.10: Buoyancy lux QHB (due o he e y low wa e apo con end du ing May 2006 equa able o he eal sensible hea lux QH) a 2.4 m abo e g ound ob ained by he eddy co a iance complex EF and he ela ed quali y lags o he S eady S a e es (Foken & Wichu a, 1996; TK2-so wa e) o he co a iance o he luc ua ions o he sonic empe a u e (Ts') and e ical (w') wind componen (s a lag_wTs). The classes 1 o 3 a e good quali y, he classes 4 o 6 a e usable quali y, class 7 and 8 a e only o o ien a ion, 9 has o be neglec ed, May 7 o May 19, 2006. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. 65 Ny-Alesund 0 1 2 3 4 5 6 7 8 9 10 07 08 09 10 11 12 13 14 15 16 17 18 19 20 Time [Day] i c (σT / T∗) quali y lag -40 -30 -20 -10 0 10 20 30 40 May 2006 QHB [W m−2] buoyancy lux i c lag_Ts Figu e 5.11: Buoyancy lux QHB (due o he e y low wa e apo con end du ing May 2006 equa able o he eal sensible hea lux QH) a 2.4 m abo e g ound ob ained by he eddy co a iance complex EF and he ela ed quali y lags o he In eg al Tu bulence Cha ac e is ic es (ITC- es , Foken & Wichu a, 1996; TK2- so wa e) o he s anda d de ia ion (σTs) no malized by i s dynamical pa ame e T∗ (i c lag_Ts). The classes 1 o 3 a e good quali y, he classes 4 o 6 a e usable quali y, class 7 and 8 a e only o o ien a ion, 9 has o be neglec ed, May 7 o May 19, 2006. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. Ny-Alesund May 2006 0 10 20 30 40 50 60 70 80 123456789 class % s a lag_wTs s a lag_us a Ny-Alesund May 2006 0 10 20 30 40 50 60 70 80 123456789 class % i c lag_Ts i c lag_w Figu e 5.12: Quali y con ol using he quali y lag sys em a e Foken & Wichu a (1996) by applying he TK2-so wa e. Le : S eady S a e es o he co a iance o he luc ua ions o a) he ho izon al wind componen s (u', ') and b) he sonic empe a u e (Ts') and he e ical (w') wind componen (s a lag_us a and s a lag_wTs). Righ : In eg al Tu bulence Cha ac e is ic es (ITC- es ) o he s anda d de ia ions (σw and σTs) no malized by hei dynamical pa ame e s u∗ and T∗ (i c lag_w and i c lag_Ts). The classes 1 o 3 a e good quali y, he classes 4 o 6 a e usable quali y, class 7 and 8 a e only o o ien a ion, 9 has o be neglec ed, May 7 o May 19, 2006. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. 66 Ny-Alesund -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0 45 90 135 180 225 270 315 360 φ [°] w [m s−1] un o a ed May 2006 Ny-Alesund -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0 45 90 135 180 225 270 315 360 φ [°] w [m s−1] o a ed May 2006 Ny-Alesund -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0 2 4 6 8 10 12 h [m s−1] w [m s−1] un o a ed May 2006 Ny-Alesund -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0 2 4 6 8 10 12 h [m s−1] w [m s−1] o a ed May 2006 Figu e 5.13: Quali y con ol o he u bulen luxes ob ained by he eddy co a iance complex EF applying he Plana Fi coo dina e o a ion me hod a e Wilczak e al. (2001) ideally esul ing in a w- alue o ze o a e aged o e he whole da a se May 7 o May 18, 2006. The plo s show he co ec ion e ec (le wi h un o a ed, igh wi h o a ed coo dina e ma ix) ega ding he e ical wind componen w in ela ion o he acco ding wind di ec ion φ (abo e) and ega ding he e ical wind componen w in ela ion o he acco ding ho izon al wind speed h (below). Ny-Ålesund (S alba d), ARCTEX-2006 campaign. 67 Ny-Alesund -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 Time [Day] z/L ζ [ ] -40 -30 -20 -10 0 10 20 30 40 07 08 09 10 11 12 13 14 15 16 17 18 19 20 May 2006 QHB [W m−2] s abili y z/L buoyancy lux Figu e 5.14: Buoyancy lux QHB (due o he e y low wa e apo con end du ing May 2006 equa able o he eal sensible hea lux QH) a 2.4 m abo e g ound (black do s) and he ela ed a mosphe ic s abili y pa ame e ζ (z/L), whe eas L is he Obukho -leng h and z is he measu emen heigh (2.4 m), bo h ob ained by he eddy co a iance complex EF. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. Ny-Alseund -40 -30 -20 -10 0 10 20 10 11 12 13 14 15 16 17 18 19 Time [Day] QHB [W m−2] -40 -30 -20 -10 0 10 20 May 2006 Ec SLS Qh 5.6m-0.7m SLS Qh Ri Figu e 5.15: Compa ison o he sensible hea lux ob ained by ow independen measu emen sys ems du ing May 7 and May 19, 2006, nea by Ny-Ålesund (S alba d). The g ey line (Ec ) indica es he sensible hea lux QH a 2.4 m abo e g ound ob ained by he eddy co a iance complex EF using a Campbell CAST3. The solid and do ed black lines indica es he sensible hea lux along a 104 m long lase scin illome e pa hway (Scin ec SLS-20) 1.5 m abo e g ound co e ing he same e ch as he sonic- anemome e . Fo he solid line (SLS QH Ri) he bulk Richa dson numbe was used and o he do ed line (SLS QH 5.6m−0.7m) he e ical g adien o ai empe a u e be ween 5.6 m and 0.7 m was used o decide he app op ia e lux di ec ions. To calcula e he Ri-Numbe and he empe a u e g adien he da a o bo h g adien owe s MT1 and MT2 we e used. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. 68 Ny-Alesund 0 45 90 135 180 225 270 315 360 07 08 09 10 11 12 13 14 15 16 17 18 19 20 Time [Day] Wind di ec ion φ [°] 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 May 2006 u∗ [m s−1] 07 08 09 10 11 12 13 14 15 16 17 18 19 20 S abili y z/L ζ [ ] -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 Figu e 5.16: Reco ded wind di ec ion φ (c osses) and he ic ion eloci y u∗ (g ey line), and he ela ed a mosphe ic s abili y pa ame e ζ (z/L, black do s, pos. alues = s able, neg. alues = uns able), whe eas L is he Obukho -leng h and z is he measu emen heigh (2.4 m), all ob ained by he eddy co a iance complex EF, May 7 o May 19, 2006. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. Ny-Alesund 0 45 90 135 180 225 270 315 360 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 CET [Hou ] Wind di ec ion φ [°] 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 May 16, 2006 u∗ [m s−1] 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 S abili y z/L ζ [ ] -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 Figu e 5.17: Reco ded wind di ec ion φ (c osses) and he ic ion eloci y u∗ (g ey line), and he ela ed a mosphe ic s abili y pa ame e ζ (z/L, black do s, pos. alues = s able, neg. alues = uns able), whe eas L is he Obukho -leng h and z is he measu emen heigh (2.4 m), all ob ained by he eddy co a iance complex EF, selec ed day May 16, 2006. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. Ny-Alesund 0 45 90 135 180 225 270 315 360 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 CET [Hou ] Wind di ec ion φ [°] 0.0 0.1 0.2 0.3 0.4 May 13, 2006 u∗ [m s−1] 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 S abili y z/L ζ [ ] -10 -8 -6 -4 -2 0 2 Figu e 5.18: Reco ded wind di ec ion φ (c osses) and he ic ion eloci y u∗ (g ey line), and he ela ed a mosphe ic s abili y pa ame e ζ (z/L, black do s, pos. alues = s able, neg. alues = uns able), whe eas L is he Obukho -leng h and z is he measu emen heigh (2.4 m), all ob ained by he eddy co a iance complex EF, selec ed day May 13, 2006. Ny-Ålesund (S alba d), ARCTEX-2006 campaign. 69 5.3 Daily cha s The igu es in his chap e p esen he wo di ec ly measu ed sensible hea luxes including he a mosphe ic s abili y pa ame e ζ (z/L) du ing he ARCTEX-2006 campaign May 7 o May 18 and he calcula ed sensible hea lux applying he model app oach o Launiainen & Cheng, 1995 (Tu b lx). Fo he la e app oach he eddy co a iance independen me eo ological measu emen s o bo h g adien owe s MT1 and MT2 as well as he BSRN-s a ion we e used. As inpu o he Tu b lx-model he equi ed g ound (snow) su ace empe a u e was ecalcula ed om he ou going longwa e adia ion alues o he nea by BSRN-s a ion. To de e mine he d ag coe icien o bulk ans e coe icien a snow/ice co e ed land su ace was assumed (QH T x Rad snow). The wo di ec app oaches u ilized a) he CSAT3 eddy co a iance complex EF (QHB Ec ) and b) he lase -scin illome e sec ion (QH SLS Ri). Fo he analysis o he scin illome e measu emen s he bulk Richa dson numbe was used o decide he app op ia e lux di ec ions ins ead he usual e ical g adien o ai empe a u e. Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 7, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 8, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec 70 Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 9, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 10, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 11, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec 71 Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 12, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 13, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 14, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec 72 Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 15, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 16, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 17, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec 73 Ny-Alesund -3 -2 -1 0 1 2 3 CET [hou ] z/L ζ [ ] -30 -20 -10 0 10 20 30 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 00 May 18, 2006 QH [W m−2] S abili y z/L Qh T x Rad snow Qh SLS Ri Qhb Ec