Abstract
This study investigates the dominant large-scale air circulations that control the winter maximum temperature distributions over Romania. We focus on the winter frequency of circulation types determined from the Grosswetter-Types (GWT) classification methods. We applied an unmixing method based on non-negative matrix factorization (NMF) to cumulative distributions of monthly absolute maximum winter temperatures recorded at 163 Romanian weather stations between 1961 and 2013. This method can determine both the form of the end-members and their contributions using only the input maximum temperature distributions, giving access to extreme temperature distributions and providing further insight about the link between thermal extremes and large-scale atmospheric circulation. For comparison, we also fitted the generalized extreme value distribution (GEV) to the time series. Our findings show that the particular shape of the Romanian Carpathians divides the territory into two distinct climatological areas (the intra-Carpathian and the extra-Carpathian). The NMF method proved that all maximum winter temperature distributions from 163 Romanian meteorological stations could be entirely explained by only four end-members (EMs). Both the NMF and the GEV distributions can be explained by the interplay between circulations and orography. Hence, different circulation types combined with different orography could produce similar extreme temperature distributions.
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References
Amihaesei VA et al (2024) Changes in snow cover climatology and its elevation dependency over Romania (1961–2020). Journal of Hydrology: Regional Studies 51:101637. https://doi.org/10.1016/j.ejrh.2023.101637
Andrade C, Leite S, Santos JA (2012) Temperature extremes in Europe: overview of their driving atmospheric patterns. Nat Hazards Earth Syst Sci 12:1671–1691. https://doi.org/10.5194/nhess-12-1671-2012
Barbu N, Georgescu F, Stefanescu V, Stefan S (2014) Large-scale mechanisms responsible for heat wave occurrence in Romania. Rom J Phys 59(9–10):1109–1126
Barbu N, Burada C, Stefan S, Georgescu F (2016a) Changes in the large-scale atmospheric circulation over Romania between 1961 and 2010 on seasonal basis. Acta Geophys 64(2):510–520. https://doi.org/10.1515/acgeo-2016-0002
Barbu N, Cuculeanu V, Stefan S (2016b) Investigation of the relationship between very warm days in Romania and large-scale atmospheric circulation using multiple linear regression approach. Theor Appl Climatol 126(1–2):273–284. https://doi.org/10.1007/s00704-015-1579-7
Barbu N, Stefan S, Georgescu F (2016c) Selecting of the spatial domain size for air circulation types over Romania in connection to climatological parameters. Rom Rep Phys 68(3):1227–1239
Beck C (2000) Zirkulationsdynamische Variabilität im Bereich Nordatlantik-Europa seit 1780 (Variability of circulation dynamics in the North-Atlantic-European region). Wurzherger Geographische Arbeite 95. Würzburg, DE (in German)
Beck C, Jacobeit J, Jones PD (2007) Frequency and within-type variations of large-scale circulation types and their effects on low-frequency climate variability in Central Europe since 1780. Int J Climatol 27:473–491
Birsan MV, Zaharia L, Chendes V, Branescu E (2012) Recent trends in streamflow in Romania (1976–2005). Rom Rep Phys 64(1):275–280
Birsan MV, Dumitrescu A (2014) Snow variability in Romania in connection to large-scale atmospheric circulation. Int J Climatol 34:134–144. https://doi.org/10.1002/joc.3671
Birsan MV, Zaharia L, Chendes V, Branescu E (2014a) Seasonal trends in Romanian streamflow. Hydrol Process 28(15):4496–4505. https://doi.org/10.1002/hyp.9961
Birsan MV, Dumitrescu A, Micu DM, Cheval S (2014b) Changes in annual temperature extremes in the Carpathians since AD 1961. Nat Hazards 74(3):1899–1910. https://doi.org/10.1007/s11069-014-1290-5
Birsan MV (2015) Trends in monthly natural streamflow in romania and linkages to atmospheric circulation in the North Atlantic. Water Resour Manag 29(9):3305–3313. https://doi.org/10.1007/s11269-015-0999-6
Birsan MV, Micu DM, Nita AI, Mateescu E, Szép R, Keresztesi Á (2019) Spatio-temporal changes in annual temperature extremes over Romania (1961–2013). Rom J Phys 64:816
Birsan MV et al (2020) Observed changes in mean and maximum monthly wind speed over Romania since AD 1961. Rom Rep Phys 72:702
Busuioc A, Dobrinescu A, Birsan MV, Dumitrescu A, Orzan A (2015) Spatial and temporal variability of climate extremes in Romania and associated large-scale mechanisms. Int J Climatol 35(7):1278–1300. https://doi.org/10.1002/joc.4054
Busuioc A et al (2016) Changes in the large-scale thermodynamic instability and connection with rain shower frequency over Romania. Verification of the Clausius-Clapeyron scaling. Int J Climatol 36:2015–2034. https://doi.org/10.1002/joc.4477
Cheval S, Birsan MV, Dumitrescu A (2014a) Climate variability in the Carpathian Mountains Region over 1961–2010. Global Planet Change 118:85–96. https://doi.org/10.1016/j.gloplacha.2014.04.005
Cheval S, Busuioc A, Dumitrescu A, Birsan MV (2014b) Spatiotemporal variability of meteorological drought in Romania using the standardized precipitation index (SPI). Clim Res 60:235–248. https://doi.org/10.3354/cr01245
Cheval S, Dumitrescu A, Birsan MV (2017) Variability of the aridity in the South-Eastern Europe over 1961–2050. CATENA 151:74–86. https://doi.org/10.1016/j.catena.2016.11.029
Coles S (2001) An introduction to statistical modeling of extreme values. Springer series in statistics. Springer, London. https://doi.org/10.1007/978-1-4471-3675-0
Croitoru AE, Piticar A, Ciupertea AF, Roșca CF (2016) Changes in heat waves indices in Romania over the period 1961–2015. Global Planet Change 146:109–121. https://doi.org/10.1016/j.gloplacha.2016.08.016
Dascalu SI et al (2016) Drought-related variables over the Bârlad basin (Eastern Romania) under climate change scenarios. CATENA 141:92–99. https://doi.org/10.1016/j.catena.2016.02.018
Dobrinescu A et al (2015) Changes in thermal discomfort indices in Romania and responsible large-scale mechanisms. Clim Res 64(3):213–226. https://doi.org/10.3354/cr01312
Dumitrescu A et al (2015) Recent climatic changes in Romania from observational data (1961–2013). Theor Appl Climatol 122(1–2):111–119. https://doi.org/10.1007/s00704-014-1290-0
Dumitrescu A, Birsan MV (2015) ROCADA: a gridded daily climatic dataset over Romania (1961–2013) for nine meteorological variables. Nat Hazards 78(2):1045–1063. https://doi.org/10.1007/s11069-015-1757-z
Heslop D, von Dobeneck T, Höcker M (2007) Using non-negative matrix factorization in the “unmixing” of diffuse reflectance spectra. Mar Geol 241:63–78
Heslop D, Dillon M (2007) Unmixing magnetic remanence curves without a priori knowledge. Geophys J Int 170:556–566
Heslop D (2015) Numerical strategies for magnetic mineral unmixing. Earth-Sci Rev 150:256–284. https://doi.org/10.1016/j.earscirev.2015.07.007
Ionita M, Rimbu N, Chelcea S, Patrut S (2013) Multidecadal variability of summer temperature over Romania and its relation with Atlantic Multidecadal Oscillation. Theor Appl Climatol 113:305–315. https://doi.org/10.1007/s00704-012-0786-8
Kalnay E et al (1996) The NCEP/NCAR 40-year reanalysis project. Bull Am Meteorol Soc 77:437–470
Manea A, Birsan MV, Tudorache G, Cărbunaru F (2016) Changes in the type of precipitation and associated cloud types in Eastern Romania (1961–2008). Atmos Res 169:357–365. https://doi.org/10.1016/j.atmosres.2015.10.020
Micu DM, Dumitrescu A, Cheval S, Nita IA, Birsan MV (2021) Temperature changes and elevation-warming relationships in the Carpathian Mountains. Int J Climatol 41(3):2154–2172. https://doi.org/10.1002/joc.6952
Micheu MM et al (2021) Influence of meteorological variables on people with cardiovascular diseases in Bucharest, Romania (2011–2012). Rom Rep Phys 73:707
Mihai G, Bîrsan MV, Dumitrescu A, Alexandru A, Mirancea I, Ivanov P, Stuparu E, Teodosiu M, Daia M (2018a) Adaptive genetic potential of European silver fir in Romania in the context of climate change. Ann For Res 61(1):95–108. https://doi.org/10.15287/afr.2018.1021
Mihai G, Mirancea I, Birsan MV, Dumitrescu A (2018b) Patterns of genetic variation in bud flushing of Abies alba populations. iForest 11(2):284–290. https://doi.org/10.3832/ifor2314-011
Mihai G et al (2020) Impact of climate change and adaptive genetic potential of norway spruce at the south–eastern range of species distribution. Agric for Meteorol 291:108040. https://doi.org/10.1016/j.agrformet.2020.108040
Mihai G et al (2021) Intraspecific growth response to drought of abies alba in the southeastern Carpathians. Forests 12(4):387. https://doi.org/10.3390/f12040387
Mihai G et al (2022a) Growth and adaptive capacity of douglas fir genetic resources from western Romania under climate change. Forests 13(5):805. https://doi.org/10.3390/f13050805
Mihai G et al (2022b) Climate change in the provenance regions of Romania over the last 70 years: implications for forest management. Forests 13(8):1203. https://doi.org/10.3390/f13081203
Nita IA, Sfîcă L, Voiculescu M, Birsan MV, Micheu MM (2022a) Changes in the global mean air temperature over land since 1980. Atmos Res 279:106392. https://doi.org/10.1016/j.atmosres.2022.106392
Nita IA, Apostol L, Patriche CV, Sfîcă L, Bojariu R, Birsan MV (2022b) Frequency of atmospheric circulation types over romania according to Jenkinson-Collison method based on two long-term reanalysis Datasets. Rom J Phys 67:812
Papathoma-Koehle M et al (2016) A common methodology for risk assessment and mapping for Southeast Europe: an application for heat wave risk in Romania. Nat Hazards 82(Suppl. 1):89–109. https://doi.org/10.1007/s11069-016-2291-3
Paterson GA, Heslop D (2015) New methods for unmixing sediment grain size data. Geochem Geophys 16(12):4494–4506. https://doi.org/10.1002/2015GC006070
Philipp A, Beck C, Huth R, Jacobeit J (2014) Development and comparison of circulation type classification using the COST733 dataset and software. Int J Climatol 36:2673–2691. https://doi.org/10.1002/joc.3920
Rimbu N, Stefan S, Necula C (2015) The variability of winter high temperature extremes in Romania and its relationship with large-scale atmospheric circulation. Theor Appl Climatol 121:121–130. https://doi.org/10.1007/s00704-014-1219-7
Rimbu N, Stefan S, Busuioc A, Georgescu F (2016) Links between blocking circulation and precipitation extremes over Romania in summer. Int J Climatol 36:369–376. https://doi.org/10.1002/joc.4353
Sfîcă L et al (2021) Cloud cover changes driven by atmospheric circulation in Europe during the last decades. Int J Climatol 41(Suppl. 1):E2211–E2230. https://doi.org/10.1002/joc.6841
Stefan S, Ghioca M, Rimbu N, Boroneant C (2004) Study of meteorological and hydrological drought in southern Romania from observational data. Int J Climatol 24(7):871–881
Stefanescu V, Stefan S (2011) Synoptic context of floods and major flash floods in Rumania during 1948–1995. Rom Rep Phys 63(4):1083–1098
Szép R et al (2018) Effects of the Eastern Carpathians on atmospheric circulations and precipitation chemistry from 2006 to 2016 at four monitoring stations (Eastern Carpathians, Romania). Atmos Res 214:311–328. https://doi.org/10.1016/j.atmosres.2018.08.009
Țîmpu S et al (2020) Tropospheric Dust and Associated atmospheric circulations over the Mediterranean region with focus on romania’s territory. Atmosphere 11:349. https://doi.org/10.3390/atmos11040349
Tomozeiu R, Busuioc A, Stefan S (2002) Changes in seasonal mean of maximum air temperature in Romania and their connection with large-scale circulation. Int J Climatol 22:1181–1196
Wilks DS (2006) Statistical methods in the atmospheric sciences. Academic Press, USA
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We thank Dr. Milena Gocić (University of Niš) for her useful comments and suggestions that improved the original manuscript.
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Necula, C., Stefan, S., Birsan, MV. et al. Maximum winter temperature over Romania in connection to atmospheric circulation. Theor Appl Climatol 155, 3861–3870 (2024). https://doi.org/10.1007/s00704-024-04854-5
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DOI: https://doi.org/10.1007/s00704-024-04854-5