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Approved for public release, distribution is unlimited / occurring most frequently. For the 217 large-error cases due to midlatitude influences, the most frequent error mechanisms were E-DCI (midlatitude), excessive response to vertical wind shear, excessive midlatitude cyclogenesis (E-MCG), insufficient midlatitude cyclogenesis (I-MCG), excessive midlatitude cyclolysis (E-MCL) and excessive midlatitude anticyclogenesis (E-MAG), which accounted for 68% of all large errors occurring in both NOGAPS and GFDN. Characteristics and symptoms of the erroneous forecast tracks and model fields are documented and illustrative case studies are presented. Proper identification and removal of the track forecast displaying an error mechanism could form a selective consensus that will be more accurate than a non-selective consensus. / Captain, United States Air Force

In the recent scenario of climate change, the natural variability and uncertainty associated with the hydrologic variables is of great concern to the community. This thesis opens up a new area of multi-disciplinary research. It is a promising field of research in hydrology and water resources that uses the information from the field of atmospheric science. A new way to identify and capture the variability and uncertainty associated with the hydrologic variables is established through this thesis. Assessment of hydroclimatic teleconnection for Indian subcontinent and its use in basin-scale hydrologic time series analysis and forecasting is the broad aim of this PhD thesis. The initial part of the thesis is devoted to investigate and establish the dependence of Indian summer monsoon rainfall (ISMR) on large-scale Oceanic-atmospheric circulation phenomena from tropical Pacific Ocean and Indian Ocean regions. El Niño-Southern Oscillation (ENSO) is the well established coupled Ocean-atmosphere mode of tropical Pacific Ocean whereas Indian Ocean Dipole (IOD) mode is the recently identified coupled Ocean-atmosphere mode of tropical Indian Ocean. Equatorial Indian Ocean Oscillation (EQUINOO) is known as the atmospheric component of IOD mode. The potential of ENSO and EQUINOO for predicting ISMR is investigated by Bayesian dynamic linear model (BDLM). A major advantage of this method is that, it is able to capture the dynamic nature of the cause-effect relationship between large-scale circulation information and hydrologic variables, which is quite expected in the climate change scenario. Another new method, proposed to capture the dependence between the teleconnected hydroclimatic variables is based on the theory of copula, which itself is quite new to the field of hydrology. The dependence of ISMR on ENSO and EQUINOO is captured and investigated for its potential use to predict the monthly variation of ISMR using the proposed method. The association of monthly variation of ISMR with the combined information of ENSO and EQUINOO, denoted by monthly composite index (MCI), is also investigated and established. The spatial variability of such association is also investigated. It is observed that MCI is significantly associated with monthly rainfall variation all over India, except over North-East (NE) India, where it is poor. Having established the hydroclimatic teleconnection at a comparatively larger scale, the hydroclimatic teleconnection for basin-scale hydrologic variables is then investigated and established. The association of large-scale atmospheric circulation with inflow during monsoon season into Hirakud reservoir, located in the state of Orissa in India, has been investigated. The strong predictive potential of the composite index of ENSO and EQUINOO is established for extreme inflow conditions. So the methodology of inflow prediction using the information of hydroclimatic teleconnection would be very suitable even for ungauged or poorly gauged watersheds as this approach does not use any information about the rainfall in the catchment. Recognizing the basin-scale hydroclimatic association with both ENSO and EQUINOO at seasonal scale, the information of hydroclimatic teleconnection is used for streamflow forecasting for the Mahanadi River basin in the state of Orissa, India, both at seasonal and monthly scale. It is established that the basin-scale streamflow is influenced by the large-scale atmospheric circulation phenomena. Information of streamflow from previous month(s) alone, as used in most of the traditional modeling approaches, is shown to be inadequate. It is successfully established that incorporation of large-scale atmospheric circulation information significantly improves the performance of prediction at monthly scale. Again, the prevailing conditions/characteristics of watershed are also important. Thus, consideration of both the information of previous streamflow and large-scale atmospheric circulations are important for basin-scale streamflow prediction at monthly time-scale. Adopting the developed approach of using the information of hydroclimatic teleconnection, hydrologic variables can be predicted with better accuracy which will be a very useful input for better management of water resources.

Abstract The diurnal cycle is a dominant mode of sea surface temperature (SST) variability in trop-ical oceans, that influences air-sea interaction and climate processes. Diurnal variability of SST generally ranges from ~0.1 to 2.0◦C and is controlled by atmospheric fluxes of heat and momentum. In the present study, the response of intraseasonal variability (ISV) of SST in the Bay of Bengal (BoB) to diurnal atmospheric forcings, during the summer monsoon of 2007, has been examined using an Ocean General Circulation Model (OGCM). The model is based on the Modular Ocean Model Version 4 (MOM4p0), having a horizontal resolution of 0.25◦ and 40 vertical levels, with a fine resolution of 5 m in the upper 60 m. Numerical experiments were conducted by forcing the model with daily and hourly atmospheric forcings to examine the SST-ISV modulation with the diurnal cycle. Additional experiments were performed to determine the relative role of diurnal cycle in solar radiation and winds on SST and mixed layer depth (MLD). Since salinity, which is decisive in SST variability, varies meridionally in the BoB, two locations were selected for analyses: one in the northern bay at 89◦E, 19◦N where salinity is lower and the other in the southern bay at 90◦E, 8◦N where salinity is higher, as well as observations are available from Research Moored Array for African-Asian-Australian Monsoon Analysis and Prediction (RAMA) buoy for comparision with model simulation. Diurnal atmospheric forcings modify SST-ISV in both southern and northern bay. SST-ISV in the southern bay, is dominantly controlled by the diurnal cycle of insolation, while in the northern bay, diurnal cycle of insolation and winds have comparable contribution. Diurnal cycle enhanced the amplitude of 3 selected intraseasonal events in the southern bay and 3 out of the 6 events in the northern bay, during the study period. In the southern bay, simulated SST variability with hourly forcing was closer to the observations from RAMA, implying that incorporating the diurnal cycle in model forcing rectifies SST-ISV. Moreover, SST obtained with diurnal forcing consists of additional fluctuations at higher frequencies within and in between intraseasonal events; such fluctuations are absent with daily forcing. The diurnal variability of SST is significant during the warming phase of intraseasonal events and reduces during the cooling phase. Diurnal amplitude of SST decreases with depth; depth dependence also being larger during the warming phase. SST-ISV modulation with diurnal forcing results from the diurnal cycle of upper ocean heat fluxes and vertical mixing. Diurnal warming and cooling result in a net gain or loss of heat in the mixed layer after a day’s cycle. When the retention (loss) of heat in the mixed layer increases with diurnal forcing during the warming (cooling) phase of intraseasonal events, the daily mean SST rise (fall) becomes higher, amplifying the intraseasonal warming (cooling). In the southern bay, SST-ISV amplification is mainly controlled by the diurnal variability of MLD, which modifies the heat fluxes. Increased intraseasonal warming with diurnal forcing results from the increase in radiative heating, due to the shoaling of the daytime mixed layer. Amplified intraseasonal cooling is dominantly con-trolled by the strengthening of sub-surface processes, due to the nocturnal deepening of mixed layer and increased temperature gradients below the mixed layer. In the northern bay, SST-ISV modulation with diurnal forcing is not as large as that in the southern bay. The mean increase in SST-ISV amplitudes with diurnal forcing is ~0.16◦C in the southern bay, while it is only ~0.03◦C in the northern bay. Reduced response of SST-ISV to diurnal forcings in the northern bay is related to the weaker diurnal variability of MLD. Salinity stratification limits diurnal variability of mixed layer in the northern bay, unlike in the southern bay. The seasonal (June - September) mean diurnal amplitude of MLD is ~15 m in the southern bay, while it is reduced to ~1.5 m in the northern bay. Diurnal variability of MLD, spanning only a few meters is not sufficient to create large modifications in mixed layer heat fluxes and SST-ISV in the northern bay. The vertical resolution of the model limits the shallowing of mixed layer to 7.5 m, thus restricting the diurnal variability of simulated MLD.

<p>Тема докторске дисертације је анализа екстремених температура ваздуха на подручју Војводине (северни део Србије), која се простире на површини од 21.506 km2. У анализи су коришћене временске серије са десет метеоролошких станица за временски период од 1951. до 2000. године. Укупно је анализирано осам параметара екстремних температура, и то: средње максималне и минималне, апсолутне максималне и минималне и дани са екстремним температурама (ледени, мразни, летњи и тропски). Истовремено, у истраживање су укључене и временске серије распона средњих максимума и минимума, као и распон средњих апсолутних максимума и минимума. Током рада анализирани су годишњи, сезонски и месечни низови претходно наведених параметара екстрема. У циљу добијања неопходних резултата, коришћено је више метода, као што су: Александерсонов тест, проста линеарна регресија, t-тест, Мен-Кендалов тест, коефицијент корелације, кластер анализа, анализа ројева тачака, хистограм и вишеструка линеарна регресија. Резултати хомогености месечних и сезонских временских серија, који су добијени коришћењем Александерсоновог теста, представљају прве резултате за простор Војводине и показују да је 26% испитиваних низова нехомогено, од којих је 11% подешено, односно хомогенизовано. Анализе параметара екстремних температура ваздуха показују тенденције пораста у последњих педесет година XX века. Посматрајући годишње низове, јављају се позитивни трендови код свих параметара (осим за ледене и мразне дане, где су трендови опадајући), међутим, једино се за средње минималне температуре може потврдити да имају сигнификантан пораст током испитиваног периода. Истовремено, зимски и пролећни трендови имају највишу тенденцију пораста, док су са друге стране јесењи трендови генерално опадајући. Анализом распона максималних и минималних температура, увидело се да максималне температуре генерално имају нешто већи пораст од минималних, а карактеристике оваквих флуктуација делимично су објашњене корелационом анализом са другим климатским елементима, који могу имати утицај на екстреме. Резултати су показали да високу корелациону повезаност (углавном преко 0,7), односно утицај на екстремне температуре имају инсолација, облачност, падавине и релативна влажност ваздуха. Интересантно је напоменути, да у већини радова који анализирају распоне максималних и минималних температура у појединим регионима, на нивоу континента или глобалном нивоу, указују на негативне трендове распона екстрема, међутим на простору Војводине годишњи распони имају благи позитиван тренд. Коришћењем вишеструке линеарне регресије, уочено је да показатељи атмосферске циркулације, односно NAO и AO индекси, објашњавају прилично висок проценат варијанси средњих и апсолутних максималних и минималних температура, током зимског, пролећног и летњег периода. Истовремено, узрок рапиднијег тренда пораста екстрема током последње декаде XX века, указује како на промене у осцилацијама других климатских елемената, тако и на промене доминације, односно учесталости појаве одређених типова атмосферске циркулације. Резултати у докторској дисертацији показују да деведесете године представљају најтоплију декаду на простору Војводине у оквиру испитиваног периода, што је највероватније повезано и са високим позитивним вредностима NAO индекса током исте декаде, које имају утицај на пораст зимских и пролећних вредности екстремних температура.</p> / <p>Tema doktorske disertacije je analiza ekstremenih temperatura vazduha na području Vojvodine (severni deo Srbije), koja se prostire na površini od 21.506 km2. U analizi su korišćene vremenske serije sa deset meteoroloških stanica za vremenski period od 1951. do 2000. godine. Ukupno je analizirano osam parametara ekstremnih temperatura, i to: srednje maksimalne i minimalne, apsolutne maksimalne i minimalne i dani sa ekstremnim temperaturama (ledeni, mrazni, letnji i tropski). Istovremeno, u istraživanje su uključene i vremenske serije raspona srednjih maksimuma i minimuma, kao i raspon srednjih apsolutnih maksimuma i minimuma. Tokom rada analizirani su godišnji, sezonski i mesečni nizovi prethodno navedenih parametara ekstrema. U cilju dobijanja neophodnih rezultata, korišćeno je više metoda, kao što su: Aleksandersonov test, prosta linearna regresija, t-test, Men-Kendalov test, koeficijent korelacije, klaster analiza, analiza rojeva tačaka, histogram i višestruka linearna regresija. Rezultati homogenosti mesečnih i sezonskih vremenskih serija, koji su dobijeni korišćenjem Aleksandersonovog testa, predstavljaju prve rezultate za prostor Vojvodine i pokazuju da je 26% ispitivanih nizova nehomogeno, od kojih je 11% podešeno, odnosno homogenizovano. Analize parametara ekstremnih temperatura vazduha pokazuju tendencije porasta u poslednjih pedeset godina XX veka. Posmatrajući godišnje nizove, javljaju se pozitivni trendovi kod svih parametara (osim za ledene i mrazne dane, gde su trendovi opadajući), međutim, jedino se za srednje minimalne temperature može potvrditi da imaju signifikantan porast tokom ispitivanog perioda. Istovremeno, zimski i prolećni trendovi imaju najvišu tendenciju porasta, dok su sa druge strane jesenji trendovi generalno opadajući. Analizom raspona maksimalnih i minimalnih temperatura, uvidelo se da maksimalne temperature generalno imaju nešto veći porast od minimalnih, a karakteristike ovakvih fluktuacija delimično su objašnjene korelacionom analizom sa drugim klimatskim elementima, koji mogu imati uticaj na ekstreme. Rezultati su pokazali da visoku korelacionu povezanost (uglavnom preko 0,7), odnosno uticaj na ekstremne temperature imaju insolacija, oblačnost, padavine i relativna vlažnost vazduha. Interesantno je napomenuti, da u većini radova koji analiziraju raspone maksimalnih i minimalnih temperatura u pojedinim regionima, na nivou kontinenta ili globalnom nivou, ukazuju na negativne trendove raspona ekstrema, međutim na prostoru Vojvodine godišnji rasponi imaju blagi pozitivan trend. Korišćenjem višestruke linearne regresije, uočeno je da pokazatelji atmosferske cirkulacije, odnosno NAO i AO indeksi, objašnjavaju prilično visok procenat varijansi srednjih i apsolutnih maksimalnih i minimalnih temperatura, tokom zimskog, prolećnog i letnjeg perioda. Istovremeno, uzrok rapidnijeg trenda porasta ekstrema tokom poslednje dekade XX veka, ukazuje kako na promene u oscilacijama drugih klimatskih elemenata, tako i na promene dominacije, odnosno učestalosti pojave određenih tipova atmosferske cirkulacije. Rezultati u doktorskoj disertaciji pokazuju da devedesete godine predstavljaju najtopliju dekadu na prostoru Vojvodine u okviru ispitivanog perioda, što je najverovatnije povezano i sa visokim pozitivnim vrednostima NAO indeksa tokom iste dekade, koje imaju uticaj na porast zimskih i prolećnih vrednosti ekstremnih temperatura.</p> / <p>This doctoral thesis deals with extreme air temperatures in Vojvodina (northern part of Serbia), which covers the area of 21,506 km2. Data series at ten meteorological stations for the period 1951- 2000 were used in the analysis. The following eight parameters of extreme temperatures were analysed: mean maximum and minimum; absolute maximum and minimum; and extreme temperature days (freezing, frosty, summer and tropical). Concurrently, the temporal series of mean maximum and minimum range were included into the research, as well as the range of mean absolute maximum and minimum. Annual, seasonal and monthly ranges of the aforementioned extreme parameters were included in the analysis. Towards obtaining important results, several methods were employed, such as Alexandersson test, simple linear regression, T-test, Mann-Kendall test, cluster analysis, scatterplot, histogram and multiple linear regressions. The results of homogenous monthly and seasonal temporal series obtained by employing Alexandersson test, being the first of the kind for Vojvodina highlighted that there were 26% non-homogenous, out of which 11% adjusted, i.e. homogenised within the analysed series. The analyses of extreme air temperature parameters trends showed increase in the last fifty years of the 20th century. Observation of annual series indicated positive trends for all parameters (except for freezing and frosty days, when the trends decreased). However, only mean minimal temperatures confirmed significant increase in the analysed period. Concurrently, winter and spring trends showed the highest increase, whereas autumn trend showed general decrease. In the course of the analysis of maximum and minimum temperature ranges, it was perceived that maximum temperatures generally showed higher increase compared to minimum, whereas the fluctuation features were partially explained by correlation analysis with other climatic elements, which might have influenced extremes. The results approved that high correlation coefficient (mainly above 0.7), i.e. the impact on extremes was perceived with insolation, cloudiness, precipitation and relative air humidity. Interestingly enough, most of the papers researching the series of maximum and minimum temperatures in certain regions, either continental or global, indicate negative trends in ranges of extremes. On the other hand, in Vojvodina the annual ranges show a moderately positive trend. The multiple linear regression technique brought to the perception that atmospheric circulation indicators, i.e. NAO and AO indices, explained the distinctly high percentage of variances in mean and absolute maximum and minimum temperatures during winter, spring and summer period. Concurrently, the cause of rapid increase in extremes during the 1990s indicated both the changes in oscillations of other climatic elements and changes in domination, i.e. frequency of certain types of atmospheric circulation. The results obtained for the doctoral dissertation indicated that the 1990s were the warmest decade in Vojvodina for the analysed period. Most probably, it was associated with high positive values of NAO index for the period, which affected winter and spring values of extreme temperatures.</p>

Indiana University-Purdue University Indianapolis (IUPUI) / Heat is one of the most important factors in our atmosphere for precipitation (thunderstorm) formation. Thermal energy from local urban land-cover is also a common source of heat in the lower atmosphere. This phenomenon is known as the urban heat island effect (UHI) and is identified as a substantial cause to a changing climate in surface weather modification. The proceeding study investigates this connection between the UHI and surface weather using remote sensing platforms A ten-year analysis of the Indianapolis UHI and thunderstorms were studied from the summer months of May, June, July, August and September (MJJAS) from 2002 until 2011. LANDSAT space borne satellite technology and land-surface based weather radar technology was used in this analysis for thunderstorm investigation. Precipitation areas identified from land-based NEXRAD WSR-88D technology were used to identify convection from non-synoptic forcing and non-normal surface diurnal heating scenarios. Only convection appearing from the UHI were studied and analyzed. Results showed twenty-one events over eighteen days with the year 2005 and 2011 having the largest frequency of events. The month of August had the largest concentration with seven events during the late afternoon hours. UHI results showed July had the largest heat island magnitude with April and September having the lowest magnitude in UHI temperatures. Three events of the twenty-one storm paths did not had a significant mean temperature difference in the heat island below the storm reflectivity. The nineteen storm paths that were significant had a warmer area underneath storm path development by an average 6.2°C than surrounding areas. UHI initiation points showed twelve of the twenty-one events having statistically significant differences between 2 km initiation areas and the rest of the study areas. Land-cover results showed low intensity developed areas had the most land-cover type (48%) in the 2km initiation buffer regions.

L’objectif principal de cette thèse est de caractériser l’atmosphère de Jupiters chaudes par spectroscopie de transmission à haute résolution, dans l’infrarouge proche, avec l’instrument SPIRou. L’historique de formation, d’évolution et de migration des planètes est empreint dans leur composition chimique, et de retrouver cette composition permet d’en élucider le mystère. La spectroscopie de transit et d’émission a prouvé être fortement efficace à cette tâche, autant pour la détermination de la composition que pour la détermination d’autres caractéristiques atmosphériques comme le profil de température et la dynamique, accessibles à haute résolution. Les Jupiter Chaudes, planètes géantes gazeuses qui orbitent très près de leur étoile, offrent des conditions d’observations très favorables pour ce type d’étude. Encore beaucoup d’éléments nous échappent quant aux processus physiques, chimiques et dynamiques qui gouvernent l’atmosphère de ces objets astronomiques. Des études détaillées de ceux-ci, telles que celles présentées dans cette thèse, sont nécessaires pour mieux comprendre ces mécanismes. Dans un premier temps, nous avons fait l’étude de deux transits de HD 189733 b, une des exoplanètes les plus étudiées. Cela nous a permis de valider nos méthodes d’analyse avec des données provenant du spectropolarimètre infrarouge à haute résolution SPIRou, installé au télescope Canada-France-Hawaii, représentant d’ailleurs la première caractérisation d’une atmosphère en spectroscopie de transit pour le SPIRou Legacy Survey. Nous avons confirmé la présence d’un signal d’eau à un niveau de signification de plus de 5σ, basé sur les résultats de test-t. Nous présentons la première analyse de spectroscopie de transit haute résolution faite par méthode de récupération, basée sur l’inférence bayésienne et appliquée à une grille de modèles SCARLET interpolée. Celle-ci a permis d’inférer une abondance de log_10[H2O] ≃ −4.4. Les résultats obtenus sont cohérents avec la littérature et indiquent que l’atmosphère de HD 189733 b est relativement claire (sans nuages) et possède un C/O super-solaire (correspondant à une formation au-delà de la ligne de glace de l’eau). Un fort décalage vers le bleu de l’absorption par l’eau a été observé, indiquant la présence de forts vents allant du côté jour vers le côté nuit ou un signal dominé par le côté soir du terminateur (limbe arrière), ou une combinaison des deux. Dans un second temps, nous présentons la première analyse à haute résolution dans l’infrarouge proche de trois transits de la très peu dense sous-Saturne WASP-127 b. Une étude récente à basse résolution a montré un spectre de transmission riche et une abondance super-solaire de CO2 dans son atmosphère. La contribution de CO et de CO2 n’a cependant pu être démêlée étant donné la couverture spectrale et la résolution limitée des données HST et de Spitzer utilisées, menant à des scénarios équiprobables de faible et fort C/O. La couverture de la bande de CO à 2.3 μm par SPIRou a permis de faire cette différenciation, et nos résultats ont exclu la présence de CO en abondance supérieure à log_10[CO] = −4.3, impliquant que le signal détecté à 4.5μm dans les données Spitzer provient majoritairement du CO2. De plus, un calcul de test-t sur les données SPIRou a confirmé la détection de H2O à un niveau ajusté de 4.9σ, mais également une détection potentielle de OH, à 2.4σ. Cette présence extrêmement inattendue de OH pourrait potentiellement être expliquée si la température du côté jour est assez grande, aidée par l’irradiation amplifiée de l’étoile qui quitte la séquence principale, ou encore par du mélange vertical. Nous présentons également la première méthode de récupération complète appliquée à la spectroscopie de transit à haute résolution, en utilisant la suite de modèles petitRADTRANS, et sur trois ensembles de données différents : les données SPIRou, les données HST et Spitzer de l’étude initiale, et les deux ensembles de données combinés. Une comparaison des différents résultats obtenus confirme que l’analyse conjointe permet d’avoir de meilleures contraintes sur les paramètres atmosphériques. Alors que l’étude initiale favorisait un fort C/O, nos résultats pointent vers un C/O très sous-solaire, produit par un C/H sous-solaire et un O/H plutôt stellaire. Les scénarios de formation qui supportent une telle composition sont ceux au-delà des lignes de glace de H2O et de CO2 (∼ 10ua), avec une accrétion supplémentaire de matériel riche en O via la migration et le croisement des lignes de glaces. L’accrétion du matériel est soit dominée par le gaz et tardive (après 5 à 7 millions d’années), ou encore, mixte (de gaz et de glaces) et plus précoce, avec un mélange cœur-enveloppe substantiel. Bien qu’il en reste beaucoup à faire, ces travaux de recherche ont démontré que la spectroscopie de transit à haute résolution dans l’infrarouge proche est utile pour explorer les conditions atmosphériques des Jupiter et sous-Saturne chaudes, et plus spécifiquement, avec l’instrument SPIRou. La combinaison de données à faible et à haute résolution s’avère un outil très puissant pour l’étude des atmosphères, et le sera encore plus avec les capacités révolutionnaires de JWST. / The main objective of this thesis is to characterize the atmosphere of hot Jupiters with high resolution transmission spectroscopy in the near-infrared with the SPIRou instrument. The formation, evolution and migration history of exoplanets is imprinted in their chemical composition, and finding this composition makes it possible to trace back this history. Transit and emission spectroscopy have proven to be highly effective for this task, in the determination of the composition, but also of other atmospheric characteristics such as the temperature profile and the dynamics, accessible at high resolution. Hot Jupiters -- gas giant planets orbiting very close to their star -- offer highly favourable observation conditions for this type of study. Many pieces of the puzzle are still missing regarding the physical, chemical and dynamical processes that govern the atmospheres of these astronomical objects, and detailed studies, such as the ones presented in this thesis, are necessary to better understand those mechanisms. First, we present the results of our analysis of two HD189733b transits, one of the most studied exoplanets to date. This study allowed to validate our analysis method with SPIRou data, a high-resolution near-infrared spectro-polarimeter installed at the Canada-France-Hawaii Telescope. It also represents the first characterization of an atmosphere with transit spectroscopy as part of the SPIRou Legacy Survey. Our results confirmed the H2O detection in the planet's atmosphere at a 5 sigma level, based on a $t$-test. We present the first analysis of a Bayesian retrieval framework applied to high-resolution transmission spectroscopy, using a grid of SCARLET models. We constrained the H2O abundance to log_10[H2O] ~ -4.4$. The results are consistent with the literature and agree on the atmosphere of HD189733b being relatively clear (without clouds) and having a super-solar C/O (corresponding to a formation beyond the H2O ice line). A strong blue shift of the water absorption signal was observed, indicative of strong day-to-night winds or a signal dominated by the terminator's evening side (trailing limb), or a combination of both. Second, we present the first high-resolution analysis in the near-infrared of three transits of the super low-density sub-Saturn WASP-127b. A recent low-resolution study showed a rich transmission spectrum and super-solar abundance of CO2 in its atmosphere. However, the contribution of CO and CO2 could not be disentangled given the limited spectral coverage and resolution of the HST and Spitzer data, leading to equiprobable low and high C/O scenarios. The coverage of the CO band at 2.3um by SPIRou made it possible to differentiate between the two cases, and our results excluded CO abundances greater than 10^(-4.3), implying that the signal at 4.5um seen in the Spitzer data mostly comes from CO2. Moreover, a t-test analysis on the SPIRou data confirmed the detection of H2O at an adjusted level of 4.9 sigma, but also a tentative detection of OH, at 2.4 sigma. The presence of OH, although extremely unexpected, could potentially be explained from a high enough dayside temperature, increased by the amplified irradiation of the star leaving the main sequence, or from vertical mixing. We also present the first full-retrieval framework applied to transmission spectroscopy at high resolution, using the petitRADTRANS model suite on three different datasets: on the SPIRou data, on the HST and Spitzer data from the original study, and on both datasets combined. A comparison of the different results obtained confirms that the joint analysis provides better constraints on the atmospheric parameters. While the initial study favored a high C/O, our results point toward a highly subsolar C/O, produced by a sub-stellar C/H and a roughly stellar O/H. Formation scenarios that support such a composition are those beyond the H2O and CO2 ice lines (~ 10ua), with further accretion of O-rich material via migration and ice lines crossing. The primordial/bulk accretion was either gas-dominated and late (after 5-7 Myr), or earlier and mixed (with gas and ice), with substantial core-enveloppe mixing. Although much remains to be done, this research work has demonstrated that high-resolution near-infrared transit spectroscopy is useful for exploring the atmospheric conditions of hot Jupiters and sub-Saturns, and more specifically, with the SPIRou instrument. The combination of low and high resolution data has shown to be a very powerful tool for such studies, and will be even more so with the revolutionary capabilities of JWST.

It was discovered several decades ago that eddy covariance measurements systematically underestimate sensible and latent heat fluxes, creating an imbalance in the surface energy budget. Since then, many studies have addressed this problem and proposed a variety of solutions to the problem, including improvements to instruments and correction methods applied during data postprocessing. However, none of these measures have led to the complete closure of the energy balance gap. The leading hypothesis is that not only surface-attached turbulent eddies but also sub-mesoscale atmospheric circulations contribute to the transport of energy in the atmospheric boundary layer, and the contribution from organized motions has been grossly neglected. The problem arises because the transport of energy through these secondary circulations cannot be captured by the standard eddy covariance method given the relatively short averaging periods of time (~30 minutes) used to compute statistics. There are various approaches to adjust the measured heat fluxes by attributing the missing energy to the sensible and latent heat flux in different proportions. However, few correction methods are based on the processes causing the energy balance gap. Several studies have shown that the magnitude of the energy balance gap depends on the atmospheric stability and the heterogeneity scale of the landscape around the measurement site. Based on this, the energy balance gap within the surface layer has already been modelled as a function of a nonlocal atmospheric stability parameter by performing a large-eddy simulation study with idealized homogeneous surfaces. We have further developed this approach by including thermal surface heterogeneity in addition to atmospheric stability in the parameterization. Specifically, we incorporated a thermal heterogeneity parameter that was shown to relate to the magnitude of the energy balance gap. For this purpose, we use a Large-Eddy Simulation dataset of 28 simulations with seven different atmospheric conditions and three heterogeneous surfaces with different heterogeneity scales as well as one homogeneous surface. The newly developed model captures very well the variability in the magnitude of the energy balance gap under different conditions. The model covers a wide range of both atmospheric stabilities and landscape heterogeneity scales and is well suited for application to eddy covariance measurements since all necessary information can be modelled or obtained from a few additional measurements.