Meteorology and Atmospheric Physics最新文献

{"title":"Variations in air-sea heat fluxes during lifetime of intense tropical cyclones over the Bay of Bengal","authors":"Pravat Rabi Naskar, Mrutyunjay Mohapatra, Gyan Prakash Singh","doi":"10.1007/s00703-024-01026-y","DOIUrl":"https://doi.org/10.1007/s00703-024-01026-y","url":null,"abstract":"<p>In this study, we have tried to find out the influence of air-sea heat fluxes (particularly the Surface Latent Heat Flux (SLHF) and the Surface Sensible Heat Flux (SSHF)) on the intensity of Intense Tropical Cyclones’ (ITCs’). We have analysed 32 ITCs which originated in the Bay of Bengal (BoB) during 1990–2019. We have used IMD best track data for track and vital parameters of ITCs. We have also used high resolution (0.25°×0.25°) ERA5 SLHF, SSHF and SST data for their variations during the lifetime of ITCs. It is observed that the SLHF_max during the whole lifetime and the study period is highly correlated with ITCs’ intensity (i.e. with the central pressure (CP) and the maximum sustained wind speed (MSW)) whereas the SSHF_max shows weak correlations with ITCs’ intensity. This suggests the strong association between the SLHF_max and ITCs intensity and strong latent heat flux exchange between the ocean and atmosphere during the whole lifetime and the study period. Similar results are observed in the pre-monsoon and the post-monsoon season. In the pre-monsoon season the association of SLHF_max with the ITCs intensity is stronger than the post-monsoon season due to strong background conditions, pointing towards the strong air-sea interaction. The SLHF_max in the growing and the decaying stage are also highly correlated with ITCs’ intensity but correlation coefficients of ITCs’ intensity with the SLHF_max in the decaying stage are slightly higher than those of in the growing stage. It is also found that the SSHF_max has an appreciable correlation with ITCs’ intensity during the growing stage whereas it has negligible correlation with ITCs’ intensity during the decaying stage pointing towards the influence of sensible heat flux in the growing stage of ITCs. It is also noticed that during rapid decay (RD) the SLHF_max is highly correlated with ITCs’ intensity possibly due to cold wakes which rapidly diminishes the SLHF but during rapid intensification the SLHF does not increase so rapidly due to the sluggish WISHE feedback, hence the SLHF_max during rapid intensification (RI) is not appreciably correlated with ITCs’ intensity.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":"23 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of ERA5 rainfall data over the South Pacific Region: case study of Fiji Islands","authors":"Philip Obaigwa Sagero, Arti Pratap, Royford Magiri, Victor Ongoma, Phillip Okello","doi":"10.1007/s00703-024-01025-z","DOIUrl":"https://doi.org/10.1007/s00703-024-01025-z","url":null,"abstract":"<p>Rainfall variability has a significant impact on hydrological cycle. Understanding rainfall variability over Fiji Islands is important for decision-making in the backdrop of global warming. Reanalysis rainfall products are commonly used to overcome observed data quality challenges especially over ungauged highland areas. However, an evaluation of reanalysed datasets is important to ensure accurate and reliable climate information generated using such datasets, especially for small Island with high variable topography like Fiji. This work aims to validate the spatiotemporal performance of European Centre for Medium-Range Weather Forecasts (ECMWF) fifth-generation reanalysis rainfall (ERA5) data against ground-based station data from 19 stations for the period 1971–2020 over Fiji Islands. Correlation coefficient and difference statistics: bias, and root mean square error, are used to assess the performance of the data. Further, common Empirical Orthogonal Function (common EOFs) analysis was used to evaluate spatiotemporal performance of ERA5 datasets. The results of the station-by-station comparison shows that interpolated ERA5 annual rainfall matches the corresponding results from rain gauges remarkably well for many stations. The correlation coefficient values range from 0.5 to 0.85, while the bias spans from a negative 282 to a positive 575, and the root mean square error (RMSE) varies between 285 and 662 mm for the annual rainfall across the study area. However, there is overestimation and underestimation of the observed rainfall by ERA5 datasets. The leading common EOF principal component for annual rainfall suggests that the inter-annual variability in ERA5 dataset is generally consistent with observed station datasets, cross validation results indicated high scores (correlations of 0.82), with limited spatial variation. This work presents a reliable data assessment of the ERA5 data over Fiji Islands, indicating there is good match of the annual observed rain gauged station data and ERA5. The findings give accuracy references for further use of the ERA5 data in understanding rainfall variability and change over the region.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":"29 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of a hailstorm in the south of Minas Gerais state on October 13, 2020","authors":"Raquel Gonçalves Pereira, João Gabriel Martins Ribeiro, Enrique Vieira Mattos, Michelle Simões Reboita","doi":"10.1007/s00703-024-01020-4","DOIUrl":"https://doi.org/10.1007/s00703-024-01020-4","url":null,"abstract":"<p>On October 13th, 2020, at approximately 1940 UTC, a hailstorm struck the city of Itajubá, located in the south of the Minas Gerais state, Brazil. This hailstorm produced hail with a diameter of 5 cm causing damages in roofs of houses and shelters. In this sense, the objective of this study is to describe the synoptic-scale environment that lead to the “ingredients” necessary for the mesoscale development of the storm, and to provide a description of cloud microphysical and lightning properties. Several data sources were used in this study as: surface observations, reanalysis data, and atmospheric remote sensing information. The synoptic-scale environment conducive to storm formation was associated with an inverted trough at surface and a shortwave trough at upper-level levels, which were important to organize upward movements in the atmosphere. High reflectivity (&gt; 60 dBZ) was registered in the convective cell from 1940 to 2010 UTC, according to the São Roque radar data, indicating the presence of large raindrops and/or hail on the ground. The total lightning rates increased from the beginning of the storm, reaching ~ 80 lightning/5 min around 20 min before the hail precipitation, which occurred at 1920 UTC. This study highlights the importance of associating synoptic and physical information for understanding the environment and the main features of hailstorms. It also emphasizes the significance of producing information that can aid in nowcasting tools.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":"176 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140927542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tele-connections of atmospheric oscillations on streamflow data in Turkey","authors":"Emre Kebapcioğlu, Turgay Partal","doi":"10.1007/s00703-024-01014-2","DOIUrl":"https://doi.org/10.1007/s00703-024-01014-2","url":null,"abstract":"<p>The climate indices demonstrate temporal and spatial variability of large-scale ocean–atmosphere patterns. This study has been carried out to analyze the streamflow data in Turkey to understand the effects of climate indices such as the Southern Oscillation (SO), the North Atlantic Oscillation (NAO), and the Arctic Oscillation (AO). The periodical relationship of the streamflow data of Turkey over different atmospheric oscillations was investigated. For this purpose, the average annual and seasonal flows at the current 72 stations in other regions of Turkey have been studied. In this context, the correlation analysis determined the relationship between NAO, AO, SO indices, and stream-flows. Besides, the original observed data were separated into parts by discrete wavelet transform to obtain the periodic components. The correlations between the found periodical components and atmospheric indices were also examined. The correlations between the streamflow and the AO/NAO showed a strong negative relationship during the annual/winter and spring periods, especially in western Turkey. Besides, the periodic components showed us the multi-annual connections between the global indices and the streamflow data of Turkey.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":"50 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climate forecast skill and teleconnections on seasonal time scales over Central Africa based on the North American Multi-Model Ensemble (NMME)","authors":"Roméo S. Tanessong, Thierry C. Fotso-Nguemo, Samuel Kaissassou, G. M. Guenang, A. J. Komkoua Mbienda, Lucie A. Djiotang Tchotchou, Armand F. Tchinda, Derbetini A. Vondou, Wilfried M. Pokam, Pascal M. Igri, Zéphirin D. Yepdo","doi":"10.1007/s00703-024-01018-y","DOIUrl":"https://doi.org/10.1007/s00703-024-01018-y","url":null,"abstract":"<p>This study examines the skill of the North American Multi-Model Ensemble (NMME) seasonal precipitation forecast and the influence of tropical sea surface temperature (SST) anomalies and their teleconnections on precipitation prediction skill over Central Africa (CA). The skill is assessed for December–February (DJF), March–May (MAM), June–August (JJA), and September–November (SON) seasons, at 0-, 3-, and 6- month lead time. Results show that for all seasons and at all lead times, models used in this study have tendency to overestimate the observed SSTs over the tropical areas. The multi-model ensemble mean (MME) generally succeeds in capturing the spatial differences in the seasonal mean climatology of precipitation and clearly determines the bi-modal and uni-modal natures of observed precipitation over CA. The El Ninõ-Southern Oscillation 3.4 index (Ninõ3.4), Indian Ocean Dipole (IOD) western pole index (IODWP), and IOD eastern pole index (IODEP) teleconnections with tropical SST are well represented by the MME at all seasons and lead times with a pattern correlation coefficient (PCC) &gt;0.6. The quality of these teleconnections decreases when the lead time increases. The Ninõ3.4-induced precipitation’s teleconnection is better represented in MAM at all lead times, and it is found that precipitation is reinforced over northern CA during the El Ninõ years and weakened during the La Niña years. IODWP and IODEP teleconnections with CA precipitation are well represented in MAM and SON, with PCC &gt; 0.8. The IODWP and IODEP could be a very good indicators to predict the increase or decrease of precipitation in CA during MAM and SON seasons.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":"50 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observed heatwaves characteristics and variability over Saudi Arabia","authors":"F. S. Syed, M. A. Al-Azemi, A. Zamreeq, M. Nazrul Islam, A. Ghulam","doi":"10.1007/s00703-024-01010-6","DOIUrl":"https://doi.org/10.1007/s00703-024-01010-6","url":null,"abstract":"<p>Heat waves are prolonged periods of excessively hot weather, which can have significant impacts on human health, agriculture, and the environment. Climate change has been linked to an increase in the frequency, intensity, and duration of heat waves. As the global average temperature rises, heat waves are becoming more common and more severe. The Arabian Peninsula is warming at a faster rate as compared to the globe in the recent decades. In this paper, the mild, moderate, severe, and extreme heat waves defined by 85th, 90th, 95th and 99th percentile, respectively, are analyzed over Saudi Arabia using historical daily maximum and minimum temperature observations for the period 1985–2021. The large number of mild heat waves are observed all over Saudi Arabia while extreme heat waves are dominant in the northwestern region. Moderate and severe heat waves are observed less in both the Red Sea and the Arabian Gulf coastal regions. The heat waves are intense in the northern and central areas as compared to other regions of the country. Heat wave frequency, intensity and length in Saudi Arabia are in increasing trends, along with the increase in the heat wave season length. Heat wave frequency and intensity are largely observed during the ENSO La Nina and neutral phases along with NAO negative phase as well as IOD negative and neutral phases. However, further investigation is required to see the occurrence of heat waves in different climate zones over Saudi Arabia at various seasons and their teleconnection to large-scale circulations.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":"13 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140314141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal dependence of characteristics of rain drop size distribution over two different climatic zones of India","authors":"Darga Saheb Shaik, M. Venkat Ratnam, K. V. Subrahmanyam, B. L. Madhavan, K. Kishore Kumar","doi":"10.1007/s00703-024-01012-4","DOIUrl":"https://doi.org/10.1007/s00703-024-01012-4","url":null,"abstract":"<p>Raindrop size distribution (DSD) plays a significant role in understanding the microphysical process of rainfall and the quantitative precipitation estimation (QPE) in hydrology, especially in urban environments which has spatial and temporal variability. In this study, the seasonal variation in DSD and its response to cloud regimes over two contrasting coastal sites (i.e. Kolkata (22.58° N, 88.45° E) and Trivandrum (8.43° N, 76.98° E) of India obtained using laser precipitation monitor (LPM) disdrometer for more than 2 years are investigated. The results show a significant difference in DSD spectra between Kolkata and Trivandrum. It is observed that the smaller-size (&lt; 0.5 mm) particles are more dominant over Trivandrum than at Kolkata. During the monsoon, larger raindrops (D &gt; 2 mm) dominate over Kolkata when compared with Trivandrum and clear separations in DSD were observed in the pre-monsoon season. The percentage contribution of the rain types to the total rainfall duration over Kolkata (Trivandrum) is found to be about 74.13% (80.50%), 18.97% (15.35%) and 6.98% (4.13%) for stratiform, transition and convective, respectively. In the convective rain, the smaller (mid-size, 1 &lt; D &lt; 3 mm and large, D &gt; 3 mm) drops concentrations are higher (lower) over Trivandrum, while mid-size and larger (smaller, D &lt; 0.5 mm) drops are higher (lower) over Kolkata. The convective rains are dominated by continental/maritime and maritime over Kolkata and Trivandrum, respectively. As the rain rate increases, the DSD spectra have larger widths with peaks around diameter D ~ 0.5 mm over both the locations. Further, the empirical relations between reflectivity (Z) and rain rate (R) were established, which are found to be different for different rain types. In each rain type, the Z-R relationship over Kolkata (Trivandrum) is Z = 56.4*R^1.94 (Z = 21.3*R^2.18), Z = 118.8*R^1.89 (Z = 106.4*R^1.83), and Z = 388.0*R^1.54 (Z = 303.1*R^1.38) for convective, transition and stratiform rains, respectively. These results clearly indicate that the two locations are dominated by different cloud systems and microphysical processes. Therefore, the present results are expected to provide a better understanding of regional DSD variability and Z-R relationship with seasons, rain types and cloud microphysical processes, which is the significance of the present study.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":"44 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140314409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Projected change in precipitation and temperature over undivided Sudan and its major cities","authors":"A. A. A. Mohamed, P. Maharana, Shyam S. Phartyal, A. P. Dimri","doi":"10.1007/s00703-024-01017-z","DOIUrl":"https://doi.org/10.1007/s00703-024-01017-z","url":null,"abstract":"<p>This study investigates the trend in the projected rainfall and temperature over undivided Sudan and its major cities of political, trade, and agricultural significance under two different Representative Concentration Pathways (RCPs; RCP2.6 and RCP8.5). Available high-resolution datasets from the Coordinated Regional Climate Downscaling Experiment- Coordinated Output for Regional Evaluations (CORDEX-CORE) at a resolution of 25 km along with their ensemble are considered. The study analyzes projected climate conditions, with a specific emphasis on the near future (2036–2060) and far future (2071–2095). The rainfall distribution is projected to decline across South Sudan (undivided Sudan) under RCP2.6 (RCP8.5). The projected temperature is significantly increasing while rainfall is decreasing across all cities, with these trends being more pronounced under the RCP8.5 scenario. These changes could potentially result in various climate extremes such as severe heatwaves, droughts, and wildfires, which could have significant impacts on the ecosystems, agriculture, public health and ultimately, the livelihood and socio-economic condition of the people. The findings of the study will assist the governments, local administration and town planners in formulating short-term and long-term strategies for adaptation and mitigation, aimed at reducing the impacts of climate change. The study suggests specific measures to address the extreme heat and water deficit at the local scale, hence making it a valuable policy document for addressing the changing climate in undivided Sudan.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":"53 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140198998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) signatures in tropical ozone in the Upper Troposphere Lower Stratosphere (UTLS)","authors":"Oindrila Nath, Bhupendra Bahadur Singh, Ravi Kumar Kunchala","doi":"10.1007/s00703-024-01007-1","DOIUrl":"https://doi.org/10.1007/s00703-024-01007-1","url":null,"abstract":"<p>This study examines the combined influence of El Niño-Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) on Upper Troposphere Lower Stratosphere (UTLS) ozone variability. The investigation employs data from the Microwave Limb Sounder (MLS) aboard the Aura Satellite and the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 reanalysis, spanning the period 2005–2020 across tropical latitudes (20º N–20º S). Three specific events were chosen for analysis: a strong La Niña event in 2010, the co-occurrence of El Niño and moderate IOD in 2015, and a robust IOD event in 2019. During years marked by the simultaneous occurrence of ENSO and IOD events, the UTLS (100 hPa altitude is considered for the present study. 82 hPa is the altitude just above the tropopause, therefore also shown in the results) ozone mixing ratio demonstrates a decline in absolute values. The Quasi-biennial Oscillation (QBO) was also investigated, revealing a synchronized variation with the ozone anomaly in the UTLS region. Furthermore, the calculated eddy heat flux, utilized as a proxy for the Brewer–Dobson Circulation (BDC), aligns with the UTLS ozone anomalies, indicating a positive (negative) anomaly during periods of intense tropical downwelling (upwelling). To quantitatively elucidate the contributions of ENSO, IOD, and QBO to the observed ozone anomaly, a multivariate linear regression analysis was executed utilizing the least square method. The findings underscore that a notable fraction—about one-fourth of the observed UTLS ozone anomaly within the study timeframe (2005–2020) can be attributed collectively to ENSO, IOD, and QBO. This preliminary exploration underscores the substantial role played by large-scale climate drivers emanating from the Pacific and Indian oceans in shaping UTLS ozone distribution. These insights emphasize the significance of considering these climatic influences when examining the intricate dynamics and variability of UTLS ozone patterns.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":"25 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140044931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of flux footprints in fragmented, heterogeneous croplands","authors":"","doi":"10.1007/s00703-023-01004-w","DOIUrl":"https://doi.org/10.1007/s00703-023-01004-w","url":null,"abstract":"<h3>Abstract</h3> <p>An accurate quantification of fluxes from heterogeneous sites and further bifurcation into contributing homogeneous fluxes is an active field of research. Among such sites, fragmented croplands with varying surface roughness characteristics pose formidable challenges for footprint analysis. We conducted two flux monitoring experiments in fragmented croplands characterized by two dissimilar surfaces with objectives to: (i) evaluate the performance of two analytical footprint models in heterogeneous canopy considering aggregated roughness parameters and (ii) analyze the contribution of fluxes from individual surfaces under changing wind speed. A set of three eddy covariance (EC) towers (one each capturing the homogenous fluxes from individual surfaces and a third, high tower capturing the heterogeneous mixed fluxes) was used for method validation. High-quality EC fluxes that fulfill stationarity and internal turbulence tests were analyzed considering daytime, unstable conditions. In the first experiment, source area contribution from a surface is gradually reduced by progressive cut, and its effect on high-tower flux measurements is analyzed. Two footprint models (Kormann and Meixner ‘KM’; analytical solution to Lagrangian model ‘FFP’) with modified surface roughness parameters were applied under changing source area contributions. FFP model has consistently over predicted the footprints (RMSE_FFP = 0.31 m⁻¹, PBIAS_FFP = 19.00), whereas KM model prediction was gradually changed from over prediction to under prediction towards higher upwind distances (RMSE_KM = 0.02 m⁻¹, PBIAS_KM = 8.50). Sensitivity analysis revealed that the models are more sensitive to turbulent conditions than surface characteristics. This motivated to conduct the second experiment, where the fractional contribution of individual surfaces (<em>α</em> and <em>β</em>) to the heterogeneous fluxes measured by the high tower (T3) was estimated using the principle of superposition (FT3 = <em>α</em> FT1 + <em>β</em> FT2). Results showed that <em>α</em> and <em>β</em> are dynamic during daylight hours and strongly depend on mean wind speed (<em>U</em>) and friction velocity (<em>u</em>*). The contribution of fluxes from adjoining fields [1 − (<em>α</em> + <em>β</em>)] is significant beyond 80% isopleth. Our findings provide guidelines for future analysis of fluxes in heterogeneous, fragmented croplands.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":"9 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139752478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}