Double‐ITCZ as an Emergent Constraint for Future Precipitation Over Mediterranean Climate Regions in the North Hemisphere

Abstract. The realistic simulation of the summer Mediterranean climate requires not only refined spatial scales, but also an adequate representation of land-atmosphere interactions and teleconnections. Addressing all of these issues remains a challenge for most of the CMIP3/CMIP5 generation models. In this study we analyze high-resolution (~0.5° lat x lon) RCP8.5 future projections of the Geophysical Fluid Dynamics Laboratory CM2.5 model with a new incorporated land model (LM3). The simulated regional future changes suggest pronounced warming and drying over most parts of the Mediterranean. However the changes are distinctively less radical when compared with the CMIP5 multimodel ensemble. Moreover, changes over the Southeast (off the coast area of the Balkans) and Central Europe indicate not only a very modest warming, compared to the CMIP5 projections, but also wetting tendencies. The difference of CM2.5 projections of future changes over previous-generation models highlights the importance of a) a correctly projected magnitude of changes of the North Atlantic Oscillation and its regional impacts, which have the capacity to partly offset the anthropogenic warming and drying over the western and central Mediterranean; b) a refined representation of land surface-atmospheric interactions, which are a governing factor for thermal- and hydro-climate over Central and Southeastern Europe. The CM2.5 projections also indicate a maximum of warming (Levant) and drying (Asia Minor) over the eastern Mediterranean. The changes derived in this region indicate a decreasing influence of atmospheric dynamics in maintaining the regional temperature and precipitation balance and instead an increasing influence of local surface temperature on the local surface atmospheric circulation.

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Long-Term Productivity of Thirteen Lowland and Upland Switchgrass Ecotypes in the Mediterranean Region

Agronomy ◽

10.3390/agronomy10070923 ◽

2020 ◽

Vol 10 (7) ◽

pp. 923

Author(s):

Efthymia Alexopoulou ◽

Federica Zanetti ◽

Eleni G. Papazoglou ◽

Konstantinos Iordanoglou ◽

Andrea Monti

Keyword(s):

Panicum Virgatum ◽

Mediterranean Climate ◽

Biomass Crop ◽

The North ◽

Panicum Virgatum L ◽

The Usa ◽

Biomass Yields ◽

The Mediterranean ◽

Marginal Soil

Switchgrass (Panicum virgatum L.) has been identified in the USA as an ideal biomass crop, in relation to its wide environmental suitability, mainly linked to the availability of both upland and lowland ecotypes, allowing the possibility of growing this species in most of the North American region. Switchgrass is conventionally grown for forage, but more recently, it has been considered as a model biofuel crop. Early European studies on switchgrass as a bioenergy crop started in the late 1990s, when a multi-location field trial was established in Greece (Aliartos) and Italy (Ozzano) to compare the productivity of 13 switchgrass genotypes, including upland (Carthage, Blackwell, Caddo, CIR, Forestburg, SU 94-1, Summer) and lowland (Alamo, Kanlow, Pangburn, SL 93-2, SL 93-3, SL94-1) genotypes. The scope was to identify the most suitable ecotype within each environment and, possibly, the best performing variety. The trials lasted 17 years (1998–2014) in Greece and 13 years (1998–2010) in Italy. While in Italy the trial was rainfed and unfertilized, in Greece, where the soil was marginal, drip irrigation was always applied, and the plots were fertilized regularly. The biomass yields in Greece, as averages across the 17 years, were similar for the lowland and upland varieties (11.5 vs. 11.1 Mg ha−1, respectively), while in Italy, as averages across the 13 years, the differences were relevant: 15.4 vs. 11.3 Mg ha−1 for lowland and upland, respectively. Alamo (lowland) was the most productive variety, both in Greece and Italy, with average annual yields of 12.7 and 16.6 Mg ha−1, respectively; CIR in Greece (10.1 Mg ha−1) and Forestburg in Italy (9.1 Mg ha−1) (both upland) were the least productive genotypes. The present results demonstrate the good suitability of switchgrass as biomass crop for the Mediterranean climate. Despite the very marginal soil (i.e., very shallow and with a sandy texture) in the Greek trial, the application of regular fertilization and irrigation produced biomass yields above 11 Mg ha−1 (grand mean) in the present 17-year-long study.

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Revisiting the humid Roman hypothesis: novel analyses depict oscillating patterns

Climate of the Past Discussions ◽

10.5194/cpd-7-2355-2011 ◽

2011 ◽

Vol 7 (4) ◽

pp. 2355-2389 ◽

Cited By ~ 4

Author(s):

B. J. Dermody ◽

H. J. de Boer ◽

M. F. P. Bierkens ◽

S. L. Weber ◽

M. J. Wassen ◽

...

Keyword(s):

North Atlantic ◽

Large Scale ◽

Mediterranean Climate ◽

Eastern Mediterranean ◽

Low Frequency ◽

Interdisciplinary Approach ◽

Archaeological Site ◽

Roman Period ◽

Spatial And Temporal Patterns ◽

The North

Abstract. Previous studies have proposed that potential vegetation in the Mediterranean maintained a wetter climate during the Roman Period until the initiation of large scale deforestation. The reduction in evapotranspirative fluxes associated with deforestation is suggested to have caused climatic aridification leading to the establishment of the present-day Mediterranean climate. There is also evidence to indicate that during the Roman Period Mediterranean climate was influenced by low frequency fluctuations in sea level pressure over the North Atlantic, termed here: the Centennial North Atlantic Oscillation (CNAO). In order to understand the importance of each of these mechanisms and disentangle their respective signals in the proxy record, we have employed an interdisciplinary approach that exploits a range of tools and data sources. An analysis of archaeological site distribution and historical texts demonstrate that climate did not increase in aridity since the Roman Period. Using an Earth system model of intermediate complexity prescribed with a reconstruction of ancient deforestation, we find that Mediterranean climate was insensitive to deforestation in the Late Holocene. A novel analysis of a composite of proxy indicators of climatic humidity depicts spatial and temporal patterns consistent with the CNAO. The link between the CNAO during the Roman Period and climatic humidity signals manifest in our composite analysis are demonstrated using a modelling approach. Finally, we present evidence indicating that fluctuations in the CNAO contributed to triggering a societal tipping point in the Eastern Mediterranean at the end of the Roman Period.

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Topography and Climate of Iraq

10.47260/jesge/1121 ◽

2020 ◽

pp. 1-13

Author(s):

Nadhir Al-Ansari

Keyword(s):

Saudi Arabia ◽

Mediterranean Climate ◽

Daily Temperature ◽

Mountain Region ◽

The West ◽

Average Daily Temperature ◽

Average Temperature ◽

The North ◽

South Iraq ◽

Semi Arid

Iraq is located between geographic coordinates 33 00 N, 44 00 E, and occupies a total area of 437,072 square kilometers. Land forms 432,162 square kilometers while water forms 4,910 square kilometers of the total area. Iraq is bordered by Turkey from the north. Iran from the east, Syria and Syria from the west, and Saudi Arabia and Kuwait from the south. Iraq can be divided according to the nature of the land terrain into 4 regions (Mountain Region, Plateau and Hills Regions, The Mesopotamian plain and Jazera and Western Plateau). The climate is mainly of continental, subtropical semi-arid type. The mountain region is of Mediterranean climate. In general, rainfall occurs from December to February or November to April in the mountain region. During winter the average daily temperature is about 16oC dropping at night to 2oC with possibility of frost. In summer however, it is very hot with an average temperature of over 45oC during July and August dropping to 25oC at night. Keywords: Topography, Climate, Iraq.

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The Strong Precipitation of the Dry Warm Front Cyclone in Syria and Its Prediction by Data Mining Modeling

Atmosphere ◽

10.3390/atmos12121667 ◽

2021 ◽

Vol 12 (12) ◽

pp. 1667

Author(s):

Jianhong Wang ◽

Nour Alakol ◽

Xing Wang ◽

Dongpo He ◽

Kanike Raghavendra Kumar ◽

...

Keyword(s):

Mediterranean Climate ◽

Forecast Accuracy ◽

Middle Layer ◽

Forecast Model ◽

Winter Precipitation ◽

Reanalysis Data ◽

The North ◽

Warm Front ◽

The Mediterranean ◽

Upper Level

The Eastern inland of Syria has a Mediterranean climate in the north and a tropical desert climate in the south, which results in a dry south and wet north climate feature, especially in winter. The circulation dynamics analysis of 16 winter strong precipitation events shows that the key system is the dry and warm front cyclone. In most cases (81–100% of the 16 cases), the moisture content in the northern part of the cyclone is higher than that in the southern part (influenced by the Mediterranean climate zone). The humidity in the middle layer is higher than that near the surface (uplifting of the dry warm front), and the thickness of the wet layer and the vertical ascending layer obviously expands upward (as shown by the satellite cloud top reflection). These characteristics lead to the moisture thermodynamic instability in the eastern part of the cyclone (dry and warm air at low level and wet and cold air at upper level). The cyclone flow transports momentum to the local humid layer of the Mediterranean climate belt and then causes unstable conditions and strong rainfall. Considering the limitations of the Syrian ground station network, the NCEP/CFSR global reanalysis data and MODIS aqua-3 cloud parameter data are used to build a multi-source factor index of winter precipitation from 2002 to 2016. A decision tree prediction model is then established and the factors index is constructed into tree shapes by the nodes and branches through calculating rules of information entropy. The suitable tree shape models are adjusted and selected by an automated training and testing process. The forecast model can classify rainfall with a forecast accuracy of more than 90% for strong rainfall over 30 mm.

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Window Design of Naturally Ventilated Offices in the Mediterranean Climate in Terms of CO2 and Thermal Comfort Performance

Sustainability ◽

10.3390/su12020473 ◽

2020 ◽

Vol 12 (2) ◽

pp. 473 ◽

Cited By ~ 2

Author(s):

Hardi K. Abdullah ◽

Halil Z. Alibaba

Keyword(s):

Thermal Comfort ◽

Natural Ventilation ◽

Mediterranean Climate ◽

Computational Modelling ◽

Co2 Concentration ◽

The North ◽

Adaptive Thermal Comfort ◽

Adaptive Comfort ◽

The Mediterranean ◽

Window Design

Natural ventilation through window openings is an inexpensive and effective solution to bring fresh air into internal spaces and improve indoor environmental conditions. This study attempts to address the “indoor air quality–thermal comfort” dilemma of naturally ventilated office buildings in the Mediterranean climate through the effective use of early window design. An experimental method of computational modelling and simulation was applied. The assessments of indoor carbon dioxide (CO2) concentration and adaptive thermal comfort were performed using the British/European standard BS EN 15251:2007. The results indicate that when windows were opened, the first-floor zones were subjected to the highest CO2 levels, especially the north-facing window in the winter and the south-facing window in the summer. For a fully glazed wall, a 10% window opening could provide all the office hours inside category I of CO2 concentration. Such an achievement requires full and quarter window openings in the cases of 10% and 25% window-to-floor ratios (WFR), respectively. The findings of the European adaptive comfort showed that less than 50% of office hours appeared in category III with cross-ventilation. The concluding remarks and recommendations are presented.

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Predicting conifer establishment post wildfire in mixed conifer forests of the North American Mediterranean‐climate zone

Ecosphere ◽

10.1002/ecs2.1609 ◽

2016 ◽

Vol 7 (12) ◽

Cited By ~ 52

Author(s):

Kevin R. Welch ◽

Hugh D. Safford ◽

Truman P. Young

Keyword(s):

North American ◽

Mediterranean Climate ◽

Conifer Forests ◽

Mixed Conifer ◽

Climate Zone ◽

The North ◽

Mixed Conifer Forests

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Foliicolous lichens and associated lichenicolous fungi in the north-eastern Iberian Peninsula: the effect of environmental factors on distribution

The Lichenologist ◽

10.1017/s0024282905014362 ◽

2005 ◽

Vol 38 (1) ◽

pp. 55-65 ◽

Cited By ~ 2

Author(s):

Esteve LLOP ◽

Antonio GÓMEZ-BOLEA

Keyword(s):

Environmental Factors ◽

Iberian Peninsula ◽

Mediterranean Climate ◽

Lichenicolous Fungi ◽

Foliicolous Lichens ◽

The North ◽

North Eastern ◽

Climatic Features ◽

Lichen Flora

The foliicolous lichens and the environmental factors at 14 stations in Catalonia were examined and the relationships between their foliicolous flora and climatic features analysed. This information could be used to predict potential sites with foliicolous lichens in areas with a Mediterranean climate. In addition, two species new to the European lichen flora (Bacidina canariensis and Fellhanera semecarpi) are recorded, and also 8 species new to the lichen and lichenicolous flora of the Iberian Peninsula (Arthonia leptosperma, Byssoloma diederichii, Chionosphaera apobasidialis, Cladosporium arthoniae, Fellhanera christiansenii, Fellhanera seroexspectata, Strigula smaragdula and Vezdaea dawsoniae).

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Mid-Holocene emergence of a low-frequency millennial oscillation in western Mediterranean climate: Implications for past dynamics of the North Atlantic atmospheric westerlies

The Holocene ◽

10.1177/0959683612460783 ◽

2012 ◽

Vol 23 (2) ◽

pp. 153-166 ◽

Cited By ~ 98

Author(s):

William J Fletcher ◽

Maxime Debret ◽

Maria Fernanda Sanchez Goñi

Keyword(s):

Ocean Circulation ◽

North Atlantic ◽

Late Holocene ◽

Mediterranean Climate ◽

Zonal Flow ◽

Western Mediterranean ◽

Early Holocene ◽

Internal Oscillation ◽

The North ◽

The North Atlantic

The nature and tempo of Holocene climate variability is examined in the record of forest vegetation from western Mediterranean marine core MD95-2043. Episodes of forest decline occurred at 10.1, 9.2, 8.3, 7.4, 5.4–4.5 and 3.7–2.9 cal. ka BP, and between 1.9 cal. ka BP and the top of the record (1.3 cal. ka BP). Wavelet analysis confirms a ~900 yr periodicity prior to and during the early Holocene and the dominance of a ~1750 yr periodicity after 6 cal. ka BP. The ~900 yr periodicity has counterparts in numerous North Atlantic and Northern Hemisphere palaeoclimate records, and in solar irradiance proxies (Δ14C and 10Be), and may relate to a Sun–climate connection during the early Holocene. Comparisons between the MD95-2043 forest record and strategically located records from Morocco, Iceland, Norway and Israel suggest that the ~1750 yr mid- to late-Holocene oscillation reflects shifts between a prevailing strong and weak state of the zonal flow, with impacts similar to the positive and negative modes of the present-day North Atlantic Oscillation (NAO). The mid- to late-Holocene millennial oscillation in zonal flow appears closely coupled to North Atlantic surface ocean circulation dynamics, and may have been driven by an internal oscillation in deep-water convection strength. The findings suggest that the mid-Holocene transition in western Mediterranean climate was accompanied by a shift in the fundamental tempo of millennial-scale variability, reflecting contrasting sensitivity of the North Atlantic climate system to different forcing factors (solar versus oceanic) under deglacial and fully interglacial conditions.

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The Mesolithic in the South of France: a critical analysis

Proceedings of the Prehistoric Society ◽

10.1017/s0079497x00018533 ◽

1953 ◽

Vol 18 (1) ◽

pp. 103-120 ◽

Cited By ~ 1

Author(s):

M. A. Smith

Keyword(s):

Mediterranean Climate ◽

High Mountains ◽

The South ◽

Massif Central ◽

The North ◽

South West ◽

Mediterranean Countries ◽

The Mediterranean ◽

To Come ◽

River Valleys

At the time when the type-sites of the Dordogne were being explored French archaeologists were equally active further south in their country. From caves and surface sites in the Mediterranean provinces local landowners, doctors and clergy were collecting material which not only matched most of the palaeolithic tool forms being distinguished in the south-west of France, but was later to provide Déchelette with many of his illustrations for the neolithic and metal ages. It was not uncommon for flints, pottery and metal all to come from the same cave.These old collections, or such of them as can be traced, are the basis of what is known about the prehistory of the south of France. Unfortunately, much of the material has come down to us with very little information, apart from provenance, and although some details of excavation were carefully recorded it seems generally to have been considered that plans of caves were more informative than sections through them.Topographically the south of France consists largely of a narrow alluvial plain, stretching right round the Gulf of Lions between the Italian and Spanish frontiers and broadening out in the delta of the Rhône. Today the region is distinguished from the rest of France by its Mediterranean climate. East of the Rhône, in Provence, this coastal climate is soon modified to the north by the high mountains, but in the old province of Languedoc between the Rhône and the Pyrenees the typical Mediterranean vegetation is carried up onto the rocky limestone plateau, or Garrigue, until it reaches the barren Causses of the Massif Central. In France, the western limit of this climatic zone falls between Carcassonne and Toulouse, but eastward and to the south the Mediterranean conditions continue, so that the south French plain forms a climatic unit with the coastlands of Italy and Spain.This plain, shut in to the north by high land, is most easily accessible from the sea or coastwise from adjacent Mediterranean countries. Easy communication with the rest of France is confined to the great river valleys of the Rhône and Aude which cut through the mountains to the north and west.

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