Arid Climate Research Articles

Achieving Indoor Thermal Comfort Using AI-Controlled Shading in Hot Arid Climates in Office Buildings

Achieving Indoor Thermal Comfort Using AI-Controlled Shading in Hot Arid Climates in Office Buildings

Assessment of the Drought Risk in Constanta County, Romania

Drought poses a significant risk in many parts of the world, especially in regions reliant on agriculture. Evaluating this risk is an essential step in preventing and reducing its impact. In this context, we assess the drought intensity at six sites in Constanța County (Romania) using the de Martonne aridity index. The risk of aridity and vulnerability to drought were evaluated by the Drought Hazard Index (DHI) and Drought Risk Index (DRI), computed based on the Standardized Precipitation Index (SPI). The de Martonne index indicates a variation between the slightly arid and semi-arid climates for Adamclisi station, with periodic changes from semi-arid to arid. At Cernavodă station, we notice a passage from an arid period towards a moderately humid one (in 2005), followed by a movement in the opposite direction to the limit of the arid zone (in 2011), and a return inside the “limits” of the semi-arid to moderately arid climate. A similar variation for 2000–2018 is noticed at Medgidia, Hârșova, and Mangalia. DRI classifies two stations in the low risk to drought category and one in the moderate risk to drought class. The other two locations experience a high or very high risk of drought. The drought intensities varied in the intervals 0.503–1.109 at Constanța, 0.473–1.363 at Mangalia, 0.511–1.493 at Adamclisi, 0.438–1.602 at Hârșova, 0.307–1.687 at Medgidia, and 0.463–1.307 at Cernavodă, and the prolonged drought periods were over 99 months at all stations.

Estimating of Solar Radiation Based on Machine Learning Approaches under Algerian Desert Climate

Estimating of Solar Radiation Based on Machine Learning Approaches under Algerian Desert Climate

Performance assessment of a 30.26 kW grid-connected photovoltaic plant in Egypt

Abstract This paper presents an experimental analysis and performance evaluation of a grid-connected photovoltaic plant installed on the rooftop of the Electronics Research Institute in Cairo, Egypt. Cairo is classified as a hot-desert climate region according to the standard Koppen-Geiger climate classification system. Over a year, we monitored real-time data to assess key system performance metrics, such as energy yield, efficiencies, performance ratio, capacity factor, and losses. Based on the obtained experimental results, the highest final yield of 5.2498 hr/day was observed in the summer, whereas the lowest yield of 3.439 hr/day occurred in the winter months. The photovoltaic plant had an average annual system efficiency of 15.8%, while the photovoltaic and inverter had mean yearly efficiencies of 17.1% and 97.2%, respectively. The average annual performance ratio is 83.03%, and the capacity factor is 18.72%. The monthly total loss exhibited a linear rise alongside increasing ambient temperature and solar irradiance. The ambient temperature affected the system efficiency, photovoltaic efficiency, and performance ratio. The findings can help strengthen forecasts of future large-scale photovoltaic plants in hot desert climates. Moreover, they can guide the design, optimization, operation, and maintenance of new grid-connected photovoltaic systems.

Twisted tapes in solar chimney-earth air heat exchangers for equipment downsizing and passive cooling

Harnessing solar and geothermal energy in hot and arid climates is an effective strategy to reduce building energy consumption. This research investigates integrating Twisted Tapes (TT) into Earth Air Heat Exchanger (EAHE) pipes within a Solar Chimney (SC)-EAHE system, aiming to reduce EAHE pipe length while meeting ventilation requirements and decreasing cooling demand. Two key innovations are introduced: first, this study pioneers the integration of TT into a SC-EAHE system; second, it comprehensively explores TT geometry optimization, analyzing the effects of width ratio and rotation rate across 77 configurations. Numerical simulations are conducted in ANSYS Fluent using the k-ε RNG turbulence model to investigate thermal performance and airflow characteristics. Findings reveal that TT integration results in a 153 % increase in Nusselt number. Additionally, it is shown that a 1 m SC diameter achieves ventilation of 4.8 Air Changes per Hour (ACH) using TT with a width ratio and rotation rate of 0.5, while reducing EAHE pipe length by 2.6 %. Increasing the SC diameter to 1.25 m, with a TT width ratio of 0.6 and rotation rate of 1.25, leads to a 13 % (35 m) reduction in EAHE pipe length while meeting a minimum outlet temperature of 290.15 K and ACH requirements. However, the benefit diminishes beyond a 1.25 m SC diameter. This study contributes to understanding of integrating TT into SC-EAHE systems, addressing the critical need for sustainable energy solutions and offering a novel and energy-efficient approach for passive cooling in extreme climates.

Assessing the impact of urban parks across Köppen climatic zones: a systematic review

This review article addresses the gap in the literature concerning the role of urban parks in providing cooling effects in hot and arid climatic zones. Using systematic review and content analysis of manuscripts from 1999 to 2023 in Scopus and Web of Science databases, elements and indicators of landscape architecture and their impacts on mitigating urban heat islands (UHI) have been explored. Our data mining revealed 190 manuscripts categorized into four Köppen climatic zones: tropical/mega thermal, arid, temperate/mesothermal, and continental/microthermal. Results indicate a scarcity of studies on hardscape elements’ impact, particularly in desert and semi-arid zones, and limited recognition of landscape architecture’s role in urban park cooling, especially in hot desert climates. Green areas emerged as the most cost-effective cooling strategy, with grass planted to minimize water elements and enhance tree cooling effects. However, the lack of softscape in hot, arid zones poses a significant challenge in mitigating UHI. These findings bridge the literature gap and suggest avenues for future research, including investigating native urban tree species and optimizing park area, shape, and orientation.

Application of PV on Commercial Building Facades: An Investigation into the Impact of Architectural and Structural Features

The rapid global transition toward renewable energy necessitates innovative solar PV deployment strategies beyond conventional roof installations. In this context, commercial building facades represent an expansive yet underutilized resource for solar energy harvesting in urban areas. However, existing studies on commercial rooftop solar PV predominantly focus on European contexts, neglecting the unique design constraints and performance trade-offs present in regions such as the Middle East. This study addresses this gap by specifically investigating the impact of architectural and structural features on the utilizable facade area for PV deployment in commercial buildings within the hot desert climate of Saudi Arabia. Detailed case studies of twelve representative buildings are conducted, combining architectural drawing analysis, on-site measurements, and stakeholder surveys. The methodology identified sixteen parameters across three categories—facade functionality, orientation suitability, and surrounding obstructions—that impose technical and non-technical restrictions on photovoltaic integration 3D modeling, and irradiance simulations revealed that, on average, just 31% of the total vertical facade area remained suitable for PV systems after accounting for the diverse architectural and contextual limitations. The study considered 698 kWh/m2 of solar irradiance as the minimum threshold for PV integration. Shopping malls displayed the lowest utilizability, with near-zero potential, as extensive opaque construction, brand signage, and shading diminish viability. Offices exhibited the highest utilizability of 36%, owing to glazed facades and unobstructed surroundings. Hotels and hospitals presented intermediate potential. Overall, the average facade utilizability factor across buildings was a mere 16%, highlighting the significant hurdles imposed by contemporary envelope configurations. Orientation unsuitability further eliminated 12% of the initially viable area. Surrounding shading contributed an additional 0.92% loss. The results quantify the sensitivity of facades to aspects such as material choices, geometric complexity, building form, and urban context. While posing challenges, the building facade resource holds immense untapped potential for solar-based urban renewal. The study highlights the need for early architectural integration, facade-specific PV product development, and urban planning interventions to maximize the renewable energy potential of commercial facades as our cities rapidly evolve into smart solar energy landscapes.

АНАЛИЗ ВЛИЯНИЯ МЕТЕОРОЛОГИЧЕСКИХ УСЛОВИЙ НА ПРОДУКТИВНОСТЬ ЯРОВОЙ ПШЕНИЦЫ В 2023 ГОДУ НА ПРИМЕРЕ МЕТЕОРОЛОГИЧЕСКОЙ СТАНЦИИ ТАЙЫНША СЕВЕРО-КАЗАХСТАНСКОЙ ОБЛАСТИ

According to the results of the assessment about possible agricultural losses due to climate change, conducted as part of the preparation of the Seventh National Communication of the Republic of Kazakhstan on Climate Change, including for the North Kazakhstan region, where, according to the forecast, by 2050 a decrease in moisture supply during the growing season by 11...16 % and an increase in climate aridity by 10...15 % relative to current indicators are expected. As a result of such changes, this may lead to a decrease in the yield of spring wheat by 30...40 %. The aim of this study was to establish the relationship between the yield of Aviada spring wheat and meteorological conditions at the observation site of the Taiynsha meteorological station in the North Kazakhstan region for 2023. For this purpose, the actual meteorological parameters for the specified year were studied, such as temperature and precipitation, hydrothermal moisture coefficient (HTC), productive moisture reserves in the soil, sums of effective temperatures, as well as the growth and development characteristics of spring wheat of the Aviada variety during the vegetation period of 2023, its yield.It was found that insufficient precipitation during the critical phases of spring wheat development created stressful conditions during the grain ripening period, and, as a result, affected its yield.In addition, the shift of summer precipitation to August...September led to crop losses during and after harvesting. This article represents the results of the research internship that took place at Taiynsha meteorological station from May to August 2023.

Monitoring Salinity in Inner Mongolian Lakes Based on Sentinel-2 Images and Machine Learning

Salinity is an essential parameter for evaluating water quality and plays a crucial role in maintaining the stability of lake ecosystems, particularly in arid and semi-arid climates. Salinity responds to changes in climate and human activity, with significant impacts on water quality and ecosystem services. In this study, Sentinel-2A/B Multi-Spectral Instrument (MSI) images and quasi-synchronous field data were utilized to estimate lake salinity using machine learning approaches (i.e., XGB, CNN, DNN, and RFR). Atmospheric correction for MSI images was tested using six processors (ACOLITE, C2RCC, POLYMER, MUMM, iCOR, and Sen2Cor). The most accurate model and atmospheric correction method were found to be the extreme gradient boosting tree combined with the ACOLITE correction algorithm. These were used to develop a salinity model (N = 70, mean absolute percentage error = 9.95%) and applied to eight lakes in Inner Mongolia from 2016 to 2024. Seasonal and interannual variations were explored, along with an examination of potential drivers of salinity changes over time. Average salinities in the autumn and spring were higher than in the summer. The highest salinities were observed in the lake centers and tended to be consistent and homogeneous. Interannual trends in salinity were evident in several lakes, influenced by evaporation and precipitation. Climate factors were the primary drivers of interannual salinity trends in most lakes.

The impact of urban form on the energy efficiency of residential buildings in a hot climate. Case study: Ouargla city

Urban development is intensifying significantly in cities, mainly due to rapid population growth. However, this development is accompanied by increased vulnerability to climate change, leading to higher energy consumption. This energy demand is even more pronounced in hot climates, where temperatures are very high during the summer season. The Algerian Sahara is no exception, and is experiencing very accelerated development, which has given rise to the appearance of new urban districts, and different urban characteristics compared to the original core, which constitutes the urban form most adapted to the desert climate and in perfect harmony with the immediate environment. This study attempts to assess the effect of the different urban forms that make up the fabric of the city of Ouargla in south-east Algeria, taken as a case study, on the energy consumption of buildings in a hot climate. This research adopts a mixed approach to evaluate the energy consumption of three buildings located in three neighbourhoods with different urban characteristics. A quantitative estimate of the energy consumed for cooling during the summer season for the three typical buildings selected was simulated using DesignBuilder software, taking into account the city’s specific climatic data, as well as the urban characteristics of the three neighbourhoods selected for the study. As a result, this evaluation covers both the architectural and urban scales. For the qualitative assessment, a field survey was carried out using questionnaires to assess the quality of thermal comfort outside neighbourhoods and its impact on building interiors, and consequently on energy consumption. The results indicate the significant effect of urban form on energy consumption, confirming that the traditional form is the most appropriate to achieve better energy efficiency in a hot climate. Therefore, the research recommends taking into account various influential factors and applying design strategies, regarding urban form, from the first stage of the design process.

Activity of photosynthetic pigments and the antioxidant system in sunflower under drought stress

Background. The study is of particular importance in view of the increasing pace of global climate aridization. The article highlights the results of an experiment on the effect of drought on the physiological status of seedlings of cv. ‘Poseidon 625’ representing an important food crop – sunflower (Helianthus annuus L.). Materials and methods. The experiment included a group of control samples grown with sufficient moisture and four impact groups subjected to osmotic stress. The intensity of accumulation of lipid peroxidation products (LPP) was measured by the reaction of malondialdehyde (MDA) with thiobarbeturic acid; catalase activity was assessed by a photocolorimetric method based on the interaction between hydrogen peroxide and potassium iodide; the content of pigments (Chl a, Chl b, Сar) was calculated spectrophotometrically in acetone extract. Results. The degree of POL accumulation in the impact groups of the experiment was found to be many times higher than the values in the control samples, which was confirmed by a rapid increase in the MDA concentration in response to a growing water shortage. The accumulation of oxygen free radicals triggered the mechanisms of antioxidant protection of seedlings by synthesizing catalase, the concentration of which increased proportionally to the accumulation of POL. At the same time, the rapid accumulation of POL in the absence of irrigation and under osmotic stress of 3 and 5 atm led to a suppression of low-molecular-weight components of protection (carotenoids) and activation of their synthesis only when critical values of osmotic stress were reached. Conclusion. As a result of the experiment, catalase was identified as the main component of antioxidant protection in sunflower seedlings. Due to the activation of its synthesis, the concentrations of Chl a and Chl b decreased, attesting to the activation of the mechanisms protecting the photosynthetic activity in seedlings, and their antioxidant status.

Uncertainty in model estimates of global groundwater depth

Abstract Knowing the depth at which groundwater can be found below the land surface is critical for understanding its potential accessibility by ecosystems and society. Uncertainty in global scale water table depth (WTD) limits our ability to assess groundwater’s role in a water cycle altered by changing climate, land cover, and human water use. Global groundwater models offer a top–down pathway to gain this knowledge, but their uncertainty is currently poorly quantified. Here, we investigate four global groundwater models and reveal steady-state WTD disagreements of more than 100 m for one-third of the global land area. We find that model estimates of land areas with shallow groundwater at <10 m depth vary from 10% to 71% (mean of 23%). This uncertainty directly translates into subsequent assessments, as land areas with potential groundwater accessibility for forests, population, and areas equipped for irrigation, differ substantially depending on the chosen model. We explore reasons for these differences and find that contrary to observations, 3 out of 4 models show deeper water tables in humid than in arid climates and greatly overestimate how strongly topographic slope controls WTD. These results highlight substantial uncertainty associated with any global-scale groundwater analysis, which should be considered and ultimately reduced.

Determining the Climate Type and Calculating the Drought Index during the Rainy Months for the Stations of Diwaniya, Samawa and Nasiriya in Southern Iraq

In this research, the climate type for the rainy months (January, February, March, April, May, October, November, December) was determined for three selected stations in southern Iraq (Diwaniyah, Samawah, Nasiriyah). By calculating the drought index for each of the rainy months mentioned above using Demarton's equation described in (Mohammed, 2020) Based on climate data including temperatures in Celsius and rainfall amounts for the above-mentioned stations for the period (2000-2021) which were obtained from the Iraqi General Commission for Meteorology and Seismic Monitoring. The results showed the mastery of arid and semi-arid climate in all study stations during most of the rainy months. Except for the months of December and January, where the climate is semi-humid in the stations of Nasiriyah and Diwaniyah, respectively. As for Samawah station, the climate is arid and semi-arid during all rainy months. The results of the statistical analysis using Excel program (2010) also showed a strong positive linear correlation between the values of the drought index and the amounts of rainfall during the rainy months at the stations (Diwaniya, Samawa, Nasiriya), where the values of the correlation coefficient reached (0.961, 0.953, 0.954) respectively. As for the linear correlation between the values of the drought index and the temperatures during the rainy months, the results showed a strong negative linear correlation between them, as the values of the correlation coefficient reached (-0.821, -0.836, -0.822) at the stations (Diwaniya, Samawa, Nasiriya) respectively.

Climate-Driven vs Human-Driven Land Degradation? The Role of Urbanization and Agricultural Intensification in Italy, 1960–2030

Climate warming, agricultural intensity, and urban growth are main forces triggering land degradation in advanced economies. Being active over different spatial and temporal scales, they usually reflect—at least indirectly—the impact of additional factors, such as wellbeing, demographic dynamics, and social development, on land quality. Using descriptive statistics and a multiple regression analysis, we analyzed the impact of these three processes comparatively over a decadal scale from 1960 to 2020 at the provincial level (Nuts-3 sensu Eurostat) in Italy. We enriched the investigation with a short-term forecast for 2030, based on four simplified assumptions grounded on a purely deterministic approach. Land degradation was estimated adopting the Environmental Sensitive Area Index (ESAI) measured at the spatio-temporal scale mentioned above. Computing on multiple observations at nearly 300,000 locations all over Italy, provinces were regarded as representative spatial units of the territorial pattern of land degradation. Between 1960 and 1990, the three predictors (climate, agriculture, and urbanization) explained a relatively high proportion of variance, suggesting a modest role for any other (unobserved) factor. All of these factors were found to be highly significant predictors of land degradation intensity across provinces, the most impactful being farming intensity. The highest adjusted-R2 coefficient was observed in both 1990 and 2000, and suggests that the three predictors still reflect the most powerful drivers of land degradation in Italy at those times, with a marginal role for additional (unobserved) factors. The impact of farming intensity remained high, with the role of urbanization increasing moderately, and the role of climate aridity declining weakly between 2000 and 2010. In more recent times (2010 and 2020), and in future (2030) scenarios, the adjusted R2 diminished moderately, suggesting a non-negligible importance of external (unobserved) factors and the rising role of spatial heterogeneity. The climate factor became progressively insignificant over time, while increasing the role of urbanization systematically. The impact of farming intensity remained high and significant. These results underlie a latent shift in the spatial distribution of the level of land vulnerability in Italy toward a spatially polarized model, influenced primarily by human pressure and socioeconomic drivers and less intensively shaped by biophysical factors. Climate aridity was revealed to be more effective in the explanation of land degradation patterns in the 1960s rather than in recent observation times.

The Effects of Corn Silage and Sunflower Silage and Their Mixtures at Different Levels on the Fattening Performance of Kıvırcık Lambs

Maize silage is widely used in the nutrition of ruminants worldwide. Nevertheless, maize is expensive and difficult to grow in cold and arid climates. To investigate the effects of feeding pure maize silage and different mixtures of maize and sunflower silages on the fattening performance of lambs. In the study, 40 Kıvırcık male lambs aged 2.5-3 months and with an average live weight of 23-25 kg were used as the animal material. The experiment was carried out for 56 days in a semi-open barn. In accordance with the experimental design, animals were divided into 5 different silage groups (100 maize silage, 75 maize silage+25 sunflower silage, 50 maize silage+50 sunflower silage, 25 maize silage+75 sunflower silage, 100% sunflower silage), so that there would be 8 lambs in each group. The lambs were housed in individual compartments during the experiment and fed individually. Silages were given ad libitum, and additional 700, 900, and 1,400 g concentrated feed was given daily between the 0th and 21st, 21st and 42nd, and 42nd and 56th days, respectively. During the fattening period, the values of live weight, daily live weight gain, feed consumption, and feed conversion ratio were determined. The differences among the live weight values of different silage groups during the trial period were found to be not significant (p>0.05), and the values obtained at the end of 8 weeks varied between 35.94 and 37.44 kg. The silage consumption of lambs fed different silage types showed significant differences (p

Speculation on an early Pleistocene origin of the Parker dunes of southwest Arizona, USA

The Parker Dunes in western Arizona, USA represent the largest dune system in the Sonoran Desert. This study presents a simple 10Be-26Al cosmogenic burial age of 1.90 ± 0.20 Ma, obtained from well cuttings 240–270 m deep in Butler Valley, just east of the dune field. Given the large errors associated with burial dating, we can only speculate that this oldest known aeolian sediment within the Parker Dunes is roughly concurrent with the Bat Cave flood event ca. 2.1 Ma of the nearby Colorado River, as well as regional climatic aridity during the early Pleistocene. Since older dune deposits may be present at other locations in the Parker Dunes, its origin dates back to at least the early Pleistocene. The more important, broader implication rests in highlighting the underutilized potential of well cuttings as a sediment source for cosmogenic burial dating in aeolian research.

The Impact of Urban Roughness on Outdoor Thermal Comfort in Hot Arid Climate

The proportion of the world's population living in cities is rapidly increasing, presenting new challenges to the urban environment and quality of life. Among these challenges is the urban environment's impact on residents' outdoor thermal comfort, which can affect their health and well-being. Urban roughness, which includes building and street heights, has a significant impact on the thermal environment of urban areas. Changes in these factors cause variations in temperature distribution, wind speed, and humidity, which affect how people perceive thermal conditions. The research problem is the effect of urban roughness on outdoor thermal comfort in hot arid climate, specifically the height of buildings and the density, for a case study in (Al-Bab Al-Sharqi) in Baghdad city. Measurement method that employed the computer programs (Rino8 and Grasshopper) to calculate the thermal comfort index (UTCI) and its impact on various climatic variables. The findings revealed that the thermal comfort index and the climatic factors associated with it vary depending on the configuration of buildings.

Stem Growth and Dehydration Responses of Mediterranean Tree Species to Atmospheric and Soil Drought.

Stem growth responses to soil and atmospheric drought are critical to forecasting the tree carbon sink strength. Yet, responses of drought-prone forests remain uncertain despite global aridification trends. Stem diameter variations at an hourly resolution were monitored in five Mediterranean tree species from a mesic and a xeric site for 6 and 12 years. Stem growth and dehydration responses to soil (REW) and atmospheric (VPD) drought were explored at different timescales. Annually, growth was determined by the number of growing days and hours. Seasonally, growth was bimodal (autumn growth ≈ 8%-18% of annual growth), varying among species and sites across the hydrometeorological space, while dehydration consistently responded to REW. Sub-daily, substantial growth occurred during daytime, with nighttime-to-daytime ratios ranging between 1.2 and 3.5 (Arbutus unedo ≈ Quercus faginea < Quercus ilex < Pinus halepensis in the mesic site, and Juniperus thurifera < P. halepensis in the xeric site). Overall, time windows favourable for growth were limited by soil (rather than atmospheric) drought, modulating annual and seasonal growth in Mediterranean species, and stems maintained non-negligible growth during daytime. These patterns contrast with observations from wetter or cooler biomes, demonstrating the growth plasticity of drought-prone species to more arid climate conditions.

Continuous and multicyclic sorption-based atmospheric water harvesting with heat recovery in arid climate

Nowadays, two-thirds of the global population are grappling with water scarcity. Sorption-based water harvesting (SAWH), which does not depend on conventional water sources and provides decentralized clean water, is steadily gaining popularity. However, the contradiction between the low daily water production in arid climates and the high energy consumption of large-scale devices has become a pivotal limitation for efficient water harvesting. Here, we report a multicyclic SAWH device with heat recovery equipped with 3 sorbent beds that alternatively desorb in automatic switching mode to achieve all-day continuous water harvesting. Furthermore, based on the rapid sorption and desorption kinetics of the adsorbent in the initial stages, employing a rapid-cycling operation strategy contributes to realize an outstanding water productivity of 8.07 kg day−1 and 0.21 kg kgsorbent−1 day−1 under practical arid conditions (15 °C/25 % RH). Besides, the apparatus equipped with heat regenerator showed a significant decrease in energy consumption from 12.17 kWh to 10.65 kWh during a desorption cycle (4 h). Moreover, a hybrid desorption mode driven by a combination of solar collector and electric heater is demonstrated in an island. This SAWH system is anticipated to provide a promising approach for large-scale efficient water harvesting in all-day arid regions (RH<35 %).

Eolian-fluvial Succession in the Early Cretaceous from the Ordos Basin

Cretaceous eolian deposits are widely developed in North China, among which the Lower Cretaceous eolian (erg) sedimentary strata in the Ordos Basin are the most representative. Many studies have been conducted on eolian deposits in the Ordos Basin, especially the Luohe Formation; however, there is a lack of systematic sedimentology research and the corresponding research on the evolution of sedimentary facies. Therefore, to explore the Mesozoic drought events and the systematic evolution of the sub-tropical erg zone, this study reports the fluvial–eolian sedimentary sequences of the Early Cretaceous Luohe and Yijinhuoluo Formations in the Ordos Basin. Spatially, through detailed sedimentary lithofacies and structural analysis of different outcrops, the combination law of sedimentary facies can be determined. Based on this, a three-dimensional sedimentary model of erg is reconstructed. The erg environment is divided into three sub-environments: erg margin, erg margin–centre transition and erg centre. According to the evolution of the sedimentary facies, the sedimentary evolution from the Late Jurassic to the Early Cretaceous in the Ordos Basin is divided into five stages. The Ordos Basin has experienced the delta, erg formation, erg deposition, erg shrinkage and evaporating salt-lake stages. The vertical sedimentary evolution indicates climatic oscillation in North China from the Late Jurassic to the Early Cretaceous. Under the control of the sub-tropical high belt, the Ordos Basin experienced a hot and arid climate during the Cretaceous, forming a widely distributed erg belt in the region. During this period, a small-scale climate shock occurred under the hot and arid background, changing the sedimentary environment.