Total Annual Rainfall Research Articles

Trend of Extreme Precipitations Indices in West-central Côte d’Ivoire: Case of the Lobo Watershed

The Lobo watershed located in the west-central part of Côte d'Ivoire is an area with high agricultural potential, influenced by climate variations and changes that reduce crop yields. The objective of this study is to analyse trends in ETCCDI extreme rainfall indices from rainfall data from 1984 to 2013 using ClimPACT2 software. This study shows that the trend of the indices: number of consecutive wet days (CWD), number of rainy days (R1mm) and the cumulative annual total rainfall (PRCPTOT) is decreasing. On the other hand, the number of consecutive dry days (CDD) is on the rise. In general, the whole basin has experienced a decrease in rainfall as well as wet sequences and an increase in dry sequences. These different trends observed in this study are more pronounced in the northern half of the watershed.

Trend of Extreme Precipitations Indices in West-central Côte d’Ivoire: Case of the Lobo Watershed

The Lobo watershed located in the west-central part of Côte d'Ivoire is an area with high agricultural potential, influenced by climate variations and changes that reduce crop yields. The objective of this study is to analyse trends in ETCCDI extreme rainfall indices from rainfall data from 1984 to 2013 using ClimPACT2 software. This study shows that the trend of the indices: number of consecutive wet days (CWD), number of rainy days (R1mm) and the cumulative annual total rainfall (PRCPTOT) is decreasing. On the other hand, the number of consecutive dry days (CDD) is on the rise. In general, the whole basin has experienced a decrease in rainfall as well as wet sequences and an increase in dry sequences. These different trends observed in this study are more pronounced in the northern half of the watershed.

Morphology and characteristics of eight Oxisols in contrasting landscapes of Costa Rica

Oxisols have been previously reported in Costa Rica. However, few studies provided specific data to corroborate their presence and explain their genesis under different soil-forming factors. This study was performed with the aim to confirm Oxisols occurrence in different landscapes and parent materials in Costa Rica. Eight pedons were sampled, described, characterized, and classified according to Soil Taxonomy in five landscapes. All pedons studied presented clay contents above 40% in surface horizons. Subsurface horizons presented red colors, high contents of low-activity clay minerals with cation exchange capacity values at pH 7 (CEC7) less than 16 cmolc kg−1 clay and less than 9.6% weatherable minerals in the sand fraction. The suborders Ustox, Udox and Perox were identified. Among the Ustox, three contrasting subgroups were identified: Kandiustalfic Eustrustox, Plinthic Kandiustox, and Anionic Acrustox. Conversely, soils classified into the suborder Udox presented the same great group: Kandiudox; with three subgroups identified: Typic Kandiudox, Plinthic Kandiudox, and Rhodic Kandiudox. In addition, one pedon was classified into the suborder Perox, with the subgroup Andic Haploperox.The diversity in geologic materials (basaltic, pyroclastic, and sedimentary rocks), geomorphology (mountains, plains, dissected volcanic cones, and Quaternary alluvial fans), and the climatic conditions (total annual rainfall ranged from 1853 to 5780 mm year−1) observed in the studied areas made possible the diverse taxonomic classification for the eight Oxisols. Results obtained confirmed occurrence of Oxisols in Costa Rica and verify soil classification from previous literature reports. Our findings in soil genesis and forming factors enhance the knowledge in pedogenesis and properties of advanced weathering stage soils in Central America.

Assessment of the impact of groundwater pumpage on water supply sustainability in Zanzibar, Tanzania

In the present study, a 42-year record of rainfall and temperature from Airport and a 43-year rainfall record from Kizimbani meteorological station were analyzed to understand how these climatic variables are affecting groundwater supply on the Island of Zanzibar, Tanzania. Water table fluctuation (WTF) and rainfall data were examined for estimating groundwater recharge. The abstraction volume and recharge rate were used to estimate the water balance. Also, the different physicochemical parameters, such as chlorinity, nitrate, electrical conductivity (EC) and total dissolved solids (TDS) were examined to assess the impact of groundwater pumpage on water quality on the island of Zanzibar. Through the use of WTF method, the present study estimated the recharge rates, local sustainable yield (SY) and integrated water balance (IWB). Rainfall records showed that Zanzibar Island receives a total mean annual rainfall of 1673 mm out of which 7% (equivalent to 1.79 × 106 m3/y) recharges the groundwater. Temperature variations indicated an incremental trend accompanied by low rainfall. The average estimated SY was 0.72%, while the IWB showed a deficit of 39%. Furthermore, the total groundwater abstraction rate in the studied area was 2.49 × 106 m3/y, which was higher than the rate of recharge. This means that the groundwater resources are currently over-exploited and, if immediate action is not taken, the groundwater aquifers may be subjected to pollution, collapse and seawater intrusion. The effects of over-pumping were manifested by high levels of EC, chloride, TDS, total hardness and nitrate that showed an increasing trend with time.

Assessment of the effect of extreme rainfall events on temporal rainfall variability in Kuwait

In recent decades, Kuwait is witnessing an increase in the number of flash floods, which puts a serious risk on human lives and properties. During November 2018, the highest extreme rainfall event was recorded in Kuwait. This paper aims at investigating the frequency of occurrence of extreme rainfall events and their effect on the temporal variability of rainfall in Kuwait. Statistical methods were implemented, such as frequency analysis of annual maximum hourly and daily rainfalls, in addition to the cumulative departure from the mean (CDM) to analyze the effect of extreme rainfall events on the temporal pattern of rainfall in Kuwait. The results show that the total annual rainfall is very wide from 31 mm in 1964 to 344 mm in 2018, while the general trend of rainfall in Kuwait is increasing with time. The statistical analysis based on developing suitable cumulative density functions for rainfall events in Kuwait shows that the return periods of the annual maximum hourly (41.5 mm/h) and the annual maximum daily (103.1 mm/day) rainfall events were 50 and 155 years, respectively. The analysis show that without the rainfall data of 2018, 49% of the CDM curve remains above the average limit of 112 mm/year. However, when the extreme rainfall events of 2018 are included in the analysis, only 11% of the CDM curve remains above the mean line of the new average limit of 116 mm. The study concluded that the rainfall pattern of Kuwait is affected considerably by extreme rainfall events and the amount of rainfall increases against reduction in number of days in the recent decades, which accordingly increases the rainfall intensities to produce more flash floods.

Climatic variability in Bhadrak district of Odisha and its characterisation

Climate variability and characterisation is very useful for understanding the current occurrence of the climate. Block wise historical rainfall data of 23 years (1995 to 2017) of Bhadrak District were collected and processed by using Weather cock software which revealed that the total mean annual rainfall of the district is 1431 mm. CV of annual rainfall in different blocks varies from 21-33%. Highest mean monthly rainfall in the district was in the month of July (286 mm) and December was the month of the lowest rainfall (4mm). Bhadrak receives almost 70% of mean annual rainfall during SW monsoon. Bhandaripokhari and Tihidi block had the highest of drought frequency (26%) followed by Dhamnagar block (21%). At 75% probability Bhadrak received 1152 mm rainfall, which is good amount of rainfall for crop production. Mean annual maximum temperature of Bhadrak district was 33oC and minimum temperature was 22.4oC. Hottest month in the district is May (37.5oC) and January was the coldest month (13.6oC). The number of occurrence of warm days in an increasing trend, while the occurrence of cold days was in decreasing trend

A statistical investigation on relationship between weather parameters and chickpea yield in Jamnagar district of Gujarat state

An attempt has been made to quantify the effect of climate change on chickpea production and relationship between weather parameters and yield of chickpea crop in Jamnagar district of Gujarat state. Crop production and productivity depend on climate in general and weather in particular. The productivity of the crop depends on soil characteristics and weather conditions during season. The present study of forecasting of gram crop yield for Jamnagar district based on weekly average data of weather parameters viz. minimum temperature (X1), maximum temperature (X2), morning relative humidity (X3), afternoon relative humidity (X4), sunshine hours (X5) and total annual rainfall of past year (X6) were analyzed for the crop weather relationship to develop regression model. The time trend (T) was also included as explanatory variable. The data pertaining for the period of 30 years weather and crop yield records of Jamnagar district were collected. The approach used for forecasting yield was original weather variables and week wise approach. The time trend was include as an explanatory variable. For this district, the model of 14 weeks period (week wise approach) was selected. Result revealed that the model of 14 weeks crop period could be suggested as a pre-harvest forecast model. The variation explained by this model was 86.17% (R2) and simulated forecast error was less than 7%. The model for Jamnagar district can be used for providing pre-harvest forecast two weeks before expected harvest.

Hydroclimate extremes in a north Australian drought reconstruction asymmetrically linked with Central Pacific Sea surface temperatures

An understanding of tropical hydroclimate variability, the associated drivers and how it is likely to change is a major scientific and societal challenge that is acutely hampered by short instrumental records. We present a 246-year tree-ring drought reconstruction of the Standardised Precipitation Evaporation Index (SPEI) for monsoonal northern Australia for the end of the wet season (March–May; MAM). This reconstruction extends the instrumental record back by 150 years. Around one third of total annual rainfall falls during MAM, making it a crucial component of the monsoonal cycle. MAM is also the season most impacted by the differential decay process of Central Pacific (as opposed to Western Pacific) El Nino events that are linked with dry conditions over northern and northwestern Australia more generally. Our reconstruction therefore provides an opportunity to consider how central Pacific variability has modulated MAM hydroclimate in Australia's monsoonal north over the past two and a half centuries. We found that MAM hydroclimate extremes in the region have a strong, but asymmetric relationship with central Pacific sea surface temperatures (SSTs) and ENSO indices. Extremely wet MAMs in monsoonal north Australia were associated with cooler SSTs, above average rainfall across much of Australia, and often coincided with La Nina events. The spatial relationship between dry extremes and Pacific SSTs during dry events was generally, but weakly, consistent with the SST signature of central Pacific El Nino events. The association between reconstructed dry extremes in the monsoonal north and dry conditions across the rest of Australia is also less extensive and weaker than for wet events. Results suggest that more extreme wet events in the Australian monsoonal north likely reflect cool central Pacific SSTs and later termination of the Australian monsoon. Consecutive years with extremely dry MAMs became more frequent over the latter part of the 20th Century while the probability of an extreme dry MAM followed by an extreme wet MAM the next year peaked in the mid 20th Century and has since declined.

Spatiotemporal variability and trends in rainfall and temperature in Alwero watershed, western Ethiopia

Climate analysis at relevant time scales is important for water resources management, agricultural planning, flood risk assessment, ecological modeling and climate change adaptation. This study analyses spatiotemporal variability and trends in rainfall and temperature in Alwero watershed, western Ethiopia. Our analysis is focused on describing spatial and temporal variability of rainfall in the study area including detection of trends, with no attempt at providing meteorological explanations to any of the patterns or trends. The study is based on gridded monthly rainfall and maximum and minimum temperature data series at a resolution of 4 × 4 km which were obtained from the National Meteorological Agency of Ethiopia for the period 1983–2016. The study area is represented by 558 points (each point representing 4 × 4 km area). Mean annual rainfall of the watershed is > 1600 mm. Annual, June–September (Kiremt), March–May (Belg) rainfall totals exhibit low inter-annual variability. Annual and October-February (Bega) rainfalls show statistically significant increasing trends at p = 0.01 level. May and November rainfall show statistically significant increasing trends at p = 0.01 level. March shows statistically significant decreasing trend at p = 0.1 level. The mean annual temperature of the watershed is 25 °C with standard deviation of 0.31 °C and coefficient of variation of 0.01 °C. Mean annual minimum and maximum temperatures show statistically non-significant decreasing trends. Bega season experienced statistically significant deceasing trend in the maximum temperature at p = 0.01 level. The year-to-year variability in the mean annual minimum and maximum temperatures showed that the 2000s is cooler than the preceding decades. Unlike our expectations, annual and seasonal rainfall totals showed increasing trends while maximum and minimum temperatures showed decreasing trends. Our results suggest that local level investigations such as this one are important in developing context-specific climate change adaptation and agricultural planning, instead of coarse-scale national level analysis guiding local level decisions.

Effects of heavy rainfall on waterborne disease hospitalizations among young children in wet and dry areas of New Zealand

Heavy rainfall is associated with increased risk of waterborne disease. However, it is not known whether the risk increment differs between wet and dry regions. We examined this question in New Zealand, which has a wide geographical variation of annual rainfall totals (10th–90th percentile difference ≥3000 mm).We conducted a nested case-crossover study within a prospective child cohort (born in 2009–2010) for assessing transient health effects when modified by longitudinal exposures to rainfall. Short-term heavy rainfall effects on hospitalizations due to enteric bacterial and viral infectious causes at lag of 0–14 days were assessed using a Cox regression model adjusted for daily temperature, relative humidity and evapotranspiration. We derived quantiles of time-weighted long-term rainfall levels at the children’s homes and these were added as an interaction term to the short-term effect model.Hospitalization risks were higher two days after heavy rainfall days (hazard ratio [95% confidence interval]: 1.73 [1.10–2.70]). The lowest-observable-adverse-effect-level was detected at the 94th percentile of daily rainfall total. Hospital admissions 1–2 days after heavy rainfall increased most in locations with the lowest and highest long-term rainfall. An interaction of this kind between short-term weather and long-term climate has not been reported previously. It is relevant to climate change risk assessments given global projections of increasing intensity of precipitation, against a background of more severe, and possibly more frequent, droughts and flooding.

Response of Kalahari vegetation to seasonal climate and herbivory: Results of 15 years of vegetation monitoring

AbstractQuestionsThe arid Kalahari is prone to desertification as a result of climate change and/or land use. We analysed the effects of climatic variables and game herbivory on the vegetation composition to answer the question of how different life‐form types respond to climate, browsers and grazers as drivers of vegetation change.LocationThe study was situated in the arid savanna of the South African Kalahari.MethodsVegetation monitoring was conducted on 20 randomly selected permanent plots (100 m2) within a biodiversity observatory. For each plot, individuals per species (abundance) were counted annually and grouped into eight life‐form types (annual and perennial graminoid and annual and perennial forb, geophyte, dwarf shrub, large shrub and tree). We ran generalised linear mixed models (GLMM) with abundance per life‐form type as response variable and a seasonal drought index (Standardised Precipitation–Evapotranspiration Index [SPEI]), total annual rainfall, year, density of large game and springbok as fixed effects, plot as random effect and year as random slope.ResultsSeasonal SPEI and density of large game and springbok had the strongest effect on abundance per life‐form type. Annual rainfall did not show any effect. The grazing large game had positive effects on the abundance of herbaceous life forms and dwarf shrubs. The predominantly browsing springbok had negative effects on perennial forbs, dwarf shrubs and trees. Directional trends in abundance per life form over time (increase of annual and decrease of perennial graminoids and forbs, increase of large shrubs) and decrease of total annual cover suggest early stages of vegetation degradation and shrub encroachment in response to both herbivory and climate.ConclusionsOur study showed that studies aimed at understanding the dynamics of arid systems should include both variance of intra‐annual climatic conditions and herbivore density as environmental drivers, related to abundance per life‐form/strategy type to reveal their specific responses to the environment.

Droughts, flooding events, and shifts in water sources and seasonality characterize last interglacial Levant climate

Modern observations document increased drought frequency together with more intense precipitation and flooding in the world’s semi-arid and arid regions as a consequence of the warming climate. Climate models predict that such conditions will intensify in the future, impacting millions of people. Paleoclimate studies can complement the short modern observational record and model projections by documenting climate changes in the past. Here we report major shifts in the geographic sources, intensity, and seasonality of Eastern Mediterranean precipitation during the unusually warm last interglacial period Marine Isotope Stage (MIS) 5e, reflecting global shifts in the rain and desert belts, based on 234U/238U-ratios in mineral precipitates in the Dead Sea, combined with evidence from climate model simulations.In the Dead Sea catchment 234U/238U ratios are indicators of water sources, where the Jordan River (flowing from the north) and the western catchments show high activity ratios between ∼1.5–1.7, and the eastern and southern catchments and flash floods (in the south-west, south and east) show lower ratios of 1.0–1.2. In Dead Sea water and precipitated minerals, 234U/238U is nearly always ∼1.45–1.55 during both glacials and interglacials. However, during the last interglacial MIS 5e insolation peak (∼127–122 ka) its value decreased to 1.2–1.3, and then to ∼1.0 towards its end (∼122–116 ka). During the insolation peak, the U-isotope data, combined with climate model runs forced with period orbital and greenhouse gas concentrations, indicate that rainfall associated with the African Summer Monsoon in the Dead Sea catchment accounted for ∼50% of the total annual rainfall, in stark contrast to present-day dry summers. The geochemical evidence indicates that following the insolation peak the region experienced an extremely dry period (although punctuated with wetter intervals), signifying expansion of the desert belt, similar to predicted effects of anthropogenic warming. This drying is partly supported by climate model runs forced with the appropriate changes in orbital parameters. The extreme drying during late MIS 5e between ∼122–116 ka reflected a major weakening of Mediterranean storm systems, resulting in a major decline of the Jordan River flow (indicated by the low 234U/238U ratios in the Dead Sea) and a relative increase in precipitation associated with the African Monsoon, shifting towards autumn. The Jordan River flow is estimated to be ∼10% of the present-day (pre-1964, prior to major diversion of the Jordan River and its sources for human use). Such changes, if they occur in the future, have serious implications for future water availability in the politically sensitive Middle East.

CLIMATOLOGY IN BARISHAL, BANGLADESH: A HISTORICAL ANALYSIS OF TEMPERATURE, RAINFALL, WIND SPEED AND RELATIVE HUMIDITY DATA

The Climatological data (temperature, rainfall, wind speed & relative humidity) recorded at Barishal divisional meteorological station and Bangladesh Meteorological Departments over the period of 1961-2019 is used for an assessment of climatological aspects, climate change and the variability of Barishal in Bangladesh. The trend of variant of yearly average maximum and minimum temperature has been found to be increasing at a rate of 0.0055 ºC & 0.0087 ºC/year. Analysis of rainfall data observed that for majority of stations, the total rainfall showed decreasing trend for pre-monsoon, monsoon and winter seasons, while little increasing trend was observed for the post-monsoon. Calculated annual total rainfall in Barishal was showed declining at the rate of -0.18488 mm/year and annual average wind speed was increasing by 0.001783 m/s per year. Likewise, yearly average relative humidity observed to be abrupt rising at a rate of 0.342975 per year with average of 70.855 at 2 meters.

English

Most studies on drivers of plant diversity and distribution have focused on trees and combine several plant families. Climbers which are part of the particular characteristics of tropical rainforests due to their richness and abundance have been rarely related to ecological factors. This study evaluates the importance of vegetation type and total annual rainfall on the distribution of the Celastraceae plant family which are mostly climbers in Côte d’Ivoire using a herbarium database. A total of 1520 samples, encompassing16 genera, 60 species and 12 varieties of Celastraceae from over 363 localities in Côte d’Ivoire, were extracted from a database on Ivorian flora. Species’ occurrences in localities were related to vegetation type and annual rainfall through a principal component analysis. A strong positive correlation (r = 0.81, P < 0.001) was found between the Celastraceae distribution and both the vegetation types and the rainfall. The Coastal evergreen and Western evergreen forests showed higher richness of Celastraceae climbers while the Sub-sudanian and Sudanian Savannas experienced lower richness than other vegetation types in Côte d’Ivoire.   Key words:  Celastraceae, Tropical forest and savanna, climbing plants, species richness and spreading, rainfall. &nbsp

O Projeto Ecolume: O paradigma da abundância na convivência com o clima semiárido no Nordeste brasileiro

O Ecolume integra as práticas dos conceitos de geração de energia fotovoltaica com a captação de águas pluviais, a reutilização de águas residuais e a produção de alimentos orgânicos ao longo do ano. A combinação de água da chuva coletada nas superfícies dos painéis solares e a reutilização de água cinza e preta, para irrigação de pomares e viveiros de mudas nativas, orienta um novo paradigma de desenvolvimento socioeconômico no semiárido, tornando este projeto um processo de adaptação eficaz às mudanças climáticas. O semiárido do Nordeste brasileiro mostrou uma redução na precipitação total anual, na forma de secas severas recorrentes. A abundância de energia solar pode ser uma fonte de desenvolvimento socioeconômico na região, ferramenta poderosa para adaptar-se às mudanças climáticas. O tratamento e a reutilização de águas cinza e negra têm como objetivo produzir água de boa qualidade para irrigar mudas em viveiro (umbu - Spondias tuberosa) e garantir a redução da poluição. A produção de mudas nativas de umbu é para reflorestar a vegetação da Caatinga (bioma local). O projeto Ecolume qualificou mais de 700 pessoas em tecnologia de energia solar, reuso e tratamento de água cinza e preta, mudas e produção de alimentos usando o sistema aquapônico.

Temporal variability and trend analysis of temperature and rainfall in the Northern highlands of Ethiopia

ABSTRACT This study investigates the temporal variability and trend of temperature and rainfall in Gelana sub-watershed, northern highlands of Ethiopia. The study employed a mixed methods approach, but overwhelmingly relied on gridded monthly rainfall and maximum and minimum temperature data at a resolution of 10 × 10 km. The quantitative data were analyzed using standardized rainfall anomaly, precipitation concentration index, coefficient of variation and Mann-Kendall (MK) trend analysis. The results indicated that rainfall over “Kiremit” and “Belg” seasons is found highly variable in the study area. The annual total rainfall has shown an increasing trend of 0.05 mm per year. The MK test results showed that “Kiremit” rainfall has a positive increasing trend, while Belg rainfall showed a statistically significant decreasing trend. A warming trend of annual maximum and minimum temperature has been observed over the study area. The study suggests strategies to enhance the adaptive capacity of agricultural systems and to reduce the likelihood of production risks.

Drought in the Eastern Cape region of South Africa and trends in rainfall characteristics.

Much of the Eastern Cape province in South Africa has been experiencing a severe drought since 2015. This drought has had major socio-economic effects particularly on the large impoverished rural population as well as on some urban areas where supplied water services have broken down in several cases. The region is influenced by both midlatitude and tropical systems leading to a complex regional meteorology that hitherto has not been much studied compared to other parts of South Africa. Here, the ongoing drought is examined in the context of long-term trends and the interannual rainfall variability of the region. Although the region has experienced drought in all seasons since 2015, focus here is placed on the spring (September–November) which shows the most consistent and robust signal. On average, this season contributes between about 25–35% of the annual rainfall total. Based on CHIRPS data, it is found that this season shows a significant decreasing trend in both rainfall totals as well as the number of rainfall days (but not heavy rainfall days) for spring over most of the province since 1981. On interannual time scales, the results indicate that dry (wet) springs over the Eastern Cape are associated with a cyclonic (anticyclonic) anomaly southeast of South Africa as part of a shift in the zonal wavenumber 3 pattern in the midlatitudes. Over the landmass, a stronger (weaker) Botswana High is also apparent with increased (decreased) subsidence over and near the Eastern Cape which is less (more) favourable for cloud band development and hence reduced (enhanced) rainfall during dry (wet) springs. Analysis of mid-century (2040–2060) CMIP5 rainfall projections suggests that there may be a flattening of the annual cycle over the Eastern Cape with the winter becoming wetter and the summer drier. For the spring season of interest here, the multi-model projections also indicate drying but less pronounced than that projected for the summer.

Individual Rainfall Change Based on Observed Hourly Precipitation Records on the Chinese Loess Plateau from 1983 to 2012

The magnitude and spatiotemporal distribution of precipitation are the main drivers of hydrologic and agricultural processes in soil moisture, runoff generation, soil erosion, vegetation growth and agriculture activities on the Loess Plateau (LP). This study detects the spatiotemporal variations of individual rainfall events during a rainy season (RS) from May to September based on the hourly precipitation data measured at 87 stations on the LP from 1983 to 2012. The incidence and contribution rates were calculated for all classes of rainfall duration and intensity to identify the dominant contribution to the rainfall amount and frequency variations. The trend rates of regional mean annual total rainfall amount (ATR) and annual mean rainfall intensity (ARI) were 0.43 mm/year and 0.002 mm/h/year in the RS for 1983–2012, respectively. However, the regional mean annual total rainfall frequency (ARF) and rainfall events (ATE) were −0.27 h/year and −0.11 times/year, respectively. In terms of spatial patterns, an increase in ATR appeared in most areas except for the southwest, while the ARI increased throughout the study region, with particularly higher values in the northwest and southeast. Areas of decreasing ARF occurred mainly in the northwest and central south of the LP, while ATE was found in most areas except for the northeast. Short-duration (≤6 h) and light rainfall events occurred mostly on the LP, accounting for 69.89% and 72.48% of total rainfall events, respectively. Long-duration (≥7 h) and moderate rainfall events contributed to the total rainfall amount by 70.64% and 66.73% of the total rainfall amount, respectively. Rainfall frequency contributed the most to the variations of rainfall amount for light and moderate rainfall events, while rainfall intensity played an important role in heavy rainfall and rainstorms. The variation in rainfall frequency for moderate rainfall, heavy rainfall, and rainstorms is mainly affected by rainfall duration, while rainfall event was identified as a critical factor for light rainfall. The characteristics in rainfall variations on the Loess Plateau revealed in this study can provide useful information for sustainable water resources management and plans.

Digging deep and running dry—the adoption of borewell technology in the face of climate change and urbanization

AbstractIn this article, we analyze the effects of household location and weather variability on the adoption of borewell technology along the rural–urban interface of Bangalore, India. Understanding these effects can help to design policies that ensure smallholders’ livelihoods and the functioning of ecosystems in drought‐prone areas. First, a theoretical framework was developed that conceptualizes how household location and weather can influence farmers’ adoption decisions. Then, an empirical analysis based on a primary data set collected in 2016 and 2017, covering 576 farm households, was conducted. With a semiparametric hazard rate model, determinants of the borewell adoption rate were analyzed. Different rainfall variables were included to capture the effect of changing climate conditions as well as a two‐dimensional penalized spline (P‐spline) to estimate the effects of household location. Results show that proximity to Bangalore, but also secondary towns accelerate adoption rates. In terms of weather variability, the study finds that a higher amount of total annual rainfall decelerates adoption rates, whereas higher amounts of rainfall during the southwest monsoon (the most important cropping season) accelerate adoption.

Variation in Atmospheric Precipitation in Poland in the Years 2001–2018

Climate change scenarios are in agreement as to the direction of air temperature changes in global warming, although the magnitude of the warming depends on the scenario adopted. In contrast, projections of changes in precipitation totals in Poland are not clear and obvious. Analysis of long-term observational series reveals no clear significant trends in levels of precipitation, despite periods of fluctuation, as well as an upward trend reported in the annual amount of precipitation, especially in northern Poland. However, the increasing variability of annual rainfall totals is commonly highlighted. In the years 1861–1990, the coefficient of variation of annual precipitation totals increased from about 10% to 16%. In the years 1971–2000, this coefficient for Poland increased to 17%, and in the period of 2001–2018, which is the subject of the present study, to 19%. Despite the lack of clear trends in annual totals, the increase in the coefficient of variation results in an increase in the frequency of both drought and floods. This unfavorable situation is exacerbated by the downward trend observed in the share of summer rainfall in the annual total. In urban areas with increasing surface sealing, the share of surface runoff in the water balance increases, and in this situation short-term rainfall will cause local flooding.