Climate Variability Change Research Articles

Performance Evaluation of High-resolution Reanalysis Datasets Over North-central British Columbia

abstract Version 2.1 of Environment and Climate Change Canada’s Canadian Surface Reanalysis (CaSR), based on the Regional Deterministic Reforecast System (RDRS), was implemented in 2022 to provide temporally complete meteorological data over 1980–2018 covering Canada at 10 km spatial resolution. Similarly, the fifth generation of the European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis-Land (ERA5-Land) dataset at ∼9 km spatial resolution became available. To assess their performance in complex topography, this paper undertakes spatiotemporal inter-comparisons between the RDRS and ERA5-Land reanalysis products with station-based data across British Columbia’s Skeena and Nechako watersheds for 1980–2018. Results reveal persistent cold biases, ranging from −6.2°C to −1.6°C basin-wide, in reanalysis mean annual air temperatures relative to observations, but biases vary in both space and time. Conversely, reanalysis total annual precipitation shows wet biases, ranging from 25% to 59% basin-wide. Analyses generally show wetting trends for observations and ERA5-Land while RDRS exhibits drying trends. Reanalysis datasets achieve better agreement overall with observations over the Nechako Watershed, likely due to its denser network of meteorological stations and less complex terrain than the Skeena Watershed. Despite some deficiencies, the RDRS and ERA5-Land reanalyses remain particularly useful products to assess regional climate variability and climatic change given their generally skilful representation of spatial patterns and temporal trends in meteorological variables across the Nechako and Skeena watersheds.

Waterborne Diseases That Are Sensitive to Climate Variability and Climate Change.

Waterborne Diseases That Are Sensitive to Climate Variability and Climate Change.

Assessing the influence of climate variability and land cover change on water resources in the Wami river catchment, Tanzania

Assessing the influence of climate variability and land cover change on water resources in the Wami river catchment, Tanzania

Long term (1901−2021) trends and prediction of climatic variability in selected agro‐ecological zones of Himachal Pradesh using coupled statistical and machine learning approaches

This study analyses the trends of changing climatic elements in the hydrological regime of the Indian Himalayan Region with specific focus on Agro‐ecological zone II & III of Himachal Pradesh for the period of 1901−2021. The upper, middle, and lower catchment areas of Sutlej River Basin were studied to reveal regional trends in climatic parameters. The Mann‐Kendall test and Sen Slope analysis were used to estimate annual and seasonal trends and their magnitude. The results showed a significant decreasing trend in the lower catchment area, with a break point year estimated to be 1953 for the entire basin. Two blocks of analysis, 1901−1953 and 1954−2021, showed significant variations. Annual rainfall data revealed a statistically significant decreasing trend at different stations. The lower catchment area received a significant increase in rainfall compared to higher altitude stations. In terms of seasonal variation, the pre‐monsoon season showed a significant decrease, while the entire basin recorded a significant increase in average monthly temperature. The study concludes by generating future time series predictions using an ANN model for the period of 2022−2050. Overall, the study's findings indicate a significant change in climatic variables with signs of increasing monthly temperatures and decreasing annual rainfall.

Cash crop farmers’ perceptions of, and adaptation to climate change: A preliminary study of Black Bush Polder, Guyana

Farmers Black Bush Polder, Guyana, have been experiencing changes in weather variability and climate parameters as well as the impacts of those changes on their livelihoods. Understanding farmers’ perception of climate change and their adaptation strategies is crucial to assisting with efforts for developing suitable intervention strategies to combat the effects of climate variability and climate change. In this non-experimental research engaging fifty (50) randomly selected farmers the aim was to: (1) examine how cash crop farmers in Black Bush Polder perceived the effects of climate change; (2) identify adaptation strategies used by farmers in combating the effects of climate change; (3) identify the factors that influence the adaptation strategies chosen by farmers; (4) identify perceived barriers in the implementation of adaptation measures; and (5) make recommendations in light of the difficulties encountered by farmers. A self-administered structured questionnaire survey was used to collect primary data and the responses to the items using a modified Likert scale. Descriptive statistics, and Pearson Correlation Coefficient were used to analyze the data. The results showed that there was variation in both temperature and rainfall in the Black Bush Polder Area. Overall, farmers had a general perception that these variations had an impact on their farming activities as well as on their choice of adaptation measures. Key recommendations made were: planting improved, or more resistant varieties of crops, changing planting times as dictated by rainfall, collection of water in furrows near plants, utilizing drip irrigation systems and techniques for preparing crop beds, and using of shade houses and greenhouses to lessen the effects of climate change.

Modeling the Effects of Climate Change and Socio-Ecomonic Variables on Agricultural Production

Modeling the Effects of Climate Change and Socio-Ecomonic Variables on Agricultural Production

Impact of climate variability and environmental policies on vegetation dynamics in the semi-arid Tigray

Anthropogenic and climate-related phenomena are among the main factors responsible for variations in vegetation structure and composition worldwide. However, studies that integrate the effects of human activities and climate variability in fragile tropical ecosystems, including the semi-arid Tigray region, are lacking. The objective of this study was to examine the effects of climate variability and environmental policy changes on the spatial distribution and pattern of vegetation cover in the semi-arid Tigray region of Ethiopia over the past four decades. We used satellite-based vegetation index (normalized difference vegetation index) and monthly rainfall data to analyze the relationship between vegetation cover and climatic variability. Residual analysis was also used to further disentangle the effects of climatic variability and environmental policy on vegetation cover. The regression analysis (r2 = 0.19) showed an insignificant causal relationship between vegetation dynamics and precipitation over the 41-years study period. This study also highlighted negative impact of the global rise in temperature on vegetation cover due to water stress caused by evapotranspiration. On the other hand, the residual analysis results (r = − 0.55, z-stat = − 11.58, p < 0.01) indicated a strong relationship between vegetation change and environmental policies implemented within the specified study period. Overall, the study revealed that environmental policies had a greater impact than climate variables on vegetation. Policymakers should, therefore, prioritize implementing effective environmental policies to restore degraded ecosystems and mitigate the effects of climate change.

Assessment of Climate Trend, Meteorological Drought and Farmers' Perception to Climate Change and Variability in Hadero Tunto District, Southern Ethiopia

Currently, climate change and variability are a hot issue, and more attention needs to be paid to their impact on Ethiopia. Farmers' perception plays a significant role in successfully implementing of adaptation strategies to reduce climate change impacts. The main objective of this study was to assess climate trends, meteorological drought and farmers' perception of climate change variability in Hadero Tunto district, Kembata Tembaro Zone, Southern Ethiopia. To determine historical climate trends, 30 years of rainfall and temperature data were obtained from the Hawassa branch of the Ethiopian National Meteorological Service, and trend analysis was performed. The multistage sampling technique was used to select 150 farm households to be surveyed. The modified Mann–Kendall and Sens' slope estimator trend tests were applied to detect the statistical significance of the trend as well as the magnitude in the time series data. The standardized precipitation index was computed for short and long-term scales to characterize the moisture content in the study area. Results of the standardized precipitation index revealed that the total number of drought events was higher in spring than summer. Still, the most extreme drought was recorded in summer. The years 1987 and 2015 experienced extreme drought in summer with indices values of -2.89 and -2.03, respectively, while, -2.27 was the spring season of 2003. In the long-term scale, -1.7 was recorded as the severe value. The historical average annual maximum and minimum temperatures both showed a significant upward trend. Historical annual rainfall shows a negligible downward trend from 1987 to 2016. This trend of rising temperatures and changing rainfall threatens smallholders´ agriculture, who are already limited by access to basic equipment and land use challenges. The descriptive result revealed that most people perceived long-term variability in the rainfall amount and distribution pattern and an increasing trend and variability of temperature. Based on these results, the study recommends that agricultural extension services be enhanced to sensitize the farmers about climate change, thus improving their perception. Further, studies at a larger scale to illustrate the associations between farmers' perceptions of climate change with meteorological data to figure out the risk of climate change are also critical

Effects of changes in climatic means, variability, and agro-technologies on future wheat and maize yields at 10 sites across the globe

To address the rising global food demand in a changing climate, yield gaps (YG), the difference between potential yields under irrigated (YP) or rainfed conditions (YWL) and actual farmers’ yields (Ya), must be significantly narrowed whilst raising potential yields. Here, we examined the likely impacts of climate change (including changes in climatic variability) and improvements in agricultural technologies on crop yields and yield gaps. Eight rigorously tested crop simulation models were calibrated for wheat and maize and run at 10 different sites around the world. Simulations were performed to estimate YP, YWL and yields achievable under three locally defined technology packages: TP0 represents average farmer's practice, while TP1 and TP2 are increasingly advanced technologies. Simulations were run for the baseline (1981–2010) and twelve future climate scenarios for 2050, representing changes in the means of climate variables and in the variability of daily temperature and dry/wet spell durations. Our basic hypotheses were that (H1) mean climate changes combined with increased weather variability lead to more negative yield impacts than mean climate changes alone, and (H2) advanced technologies would serve as effective adaptations under future climatic conditions. We found that crop responses were dependent on site characteristics, climate scenarios and adopted technologies. Our findings did not support H1. As for H2, the improved technology packages increased wheat and maize yields at all sites, but yield gap reduction varied substantially among sites. Future studies should consider a broader range of climate scenarios and methods for analysing potential shifts in climate variability. Moreover, it is recommended to co-create and evaluate climate zone-specific climate-smart crop production technologies in interaction with a wide range of local stakeholders.

Compound flood impacts from Hurricane Sandy on New York City in climate-driven storylines

Abstract. High impact events like Hurricane Sandy (2012) significantly affect society and decision-making around weather/climate adaptation. Our understanding of the potential effects of such events is limited to their rare historical occurrences. Climate change might alter these events to an extent that current adaptation responses become insufficient. Furthermore, internal climate variability in the current climate might also lead to slightly different events with possible larger societal impacts. Therefore, exploring high impact events under different conditions becomes important for (future) impact assessment. In this study, we create storylines of Sandy to assess compound coastal flooding on critical infrastructure in New York City under different scenarios, including climate change effects (on the storm and through sea level rise) and internal variability (variations in the storm's intensity and location). We find that 1 m of sea level rise increases average flood volumes by 4.2 times, while maximised precipitation scenarios (internal variability) lead to a 2.5-fold increase in flood volumes. The maximised precipitation scenarios impact inland critical infrastructure assets with low water levels, while sea level rise impacts fewer coastal assets though with high water levels. The diversity in hazards and impacts demonstrates the importance of building a set of relevant scenarios, including those representing the effects of climate change and internal variability. The integration of a modelling framework connecting meteorological conditions to local hazards and impacts provides relevant and accessible information that can directly be integrated into high impact event assessments.

Deep Learning Forecasting: An LSTM Neural Architecture based Approach to Rainfall and Flood Impact Predictions in Bihar

The increasing prominence of natural disasters and the variability in climate change have underscored the significance of research in contemporary and prospective studies. This investigation zeroes in on floods, a ubiquitous natural calamity that plagues regions globally. Bihar stands out as a state exceptionally vulnerable to persistent and intense flooding, with a staggering 69.70 lakh hectares—equivalent to nearly 74 percent of its geographical expanse—enduring its detrimental consequences. The repercussions of such inundations are widespread, permeating multiple facets of life and erecting impediments to both the welfare and the developmental trajectory of local communities. Vital sectors, including infrastructure, agriculture, and livestock, bear the brunt of the damage, catalyzing the dislocation of innumerable households. In an agile response to these adversities, the state's administrative machinery has mobilized disaster response brigades, ensuring timely aid and succor to the distressed populace. To adeptly predict impending floods, this study harnesses data from 1991 to 2022, integrating pivotal metrics such as the ’Total Population affected (in lacs)’, ’Mean Annual Rainfall’, and ’Crop damage (in INR lakhs)’. By adopting an LSTM (Long Short-Term Memory) model, the research elucidates its findings via illustrative line plots, furnishing an accessible rendition of the flood trajectory predictions over the forthcoming five-year span. These predictive insights are instrumental for disaster management agencies, enhancing their strategic planning and readied responses to imminent flood events in Bihar. Capitalizing on these forecasts enables authorities to architect proactive interventions, ensuring reduced flood repercussions, bolstered community resilience, and an elevated state of disaster preparedness in the region.

The Impact of Climate Change on Economic Growth in South Asian Countries: The Role of Financial Development, Trade Openness and Renewable Energy Consumption

This study examines the complex correlation between climate change and economic growth in South Asian nations, focusing specifically on the significant influences of financial development, trade openness, and renewable energy usage. This research endeavors to address the existing information gaps pertaining to the impact of climate change on economic development, with a specific focus on the susceptibility of South Asian nations. This study employs quantitative research approach. Economic indicators, climate data, and relevant financial and trade metrics are scrutinized to discern patterns and relationships. The methodology incorporates a multi-faceted approach to capture the complexity of the interactions between climate change variables and economic parameters. The study’s results provide significant insights into the intricate relationship among climate change, financial growth, trade openness, and renewable energy use in the South Asian region. The research elucidates how climate-induced disruptions impact economic sectors crucial to the region’s development. Moreover, it dissects the specific mechanisms through which financial structures, trade policies, and renewable energy initiatives influence economic resilience in the effect of climate challenges. Based on the findings, the study offers a set of targeted recommendations for policymakers, emphasizing the need for integrated approaches to climate change alleviation and adjustment. These recommendations encompass strategies for enhancing financial mechanisms, optimizing trade policies, and promoting sustainable practices in renewable energy consumption. By aligning economic policies with environmental sustainability goals, the recommendations aim to guide South Asian countries toward resilient and sustainable development pathways amidst the evolving landscape of climate change challenges.

Emergent Constraints on Future Changes in Several Climate Variables and Extreme Indices from Global to Regional Scales

Emergent Constraints on Future Changes in Several Climate Variables and Extreme Indices from Global to Regional Scales

Understanding the spatio-temporal distribution of bush encroachment in savannah rangelands, South Africa

Bush encroachment threatens rangelands’ biodiversity and productivity, impacting savannah ecosystems based on location, management practices, and factors like erratic rainfall, climate change, and environmental variability. Considering these challenges, this study therefore seeks to evaluate bush encroachment changes over-time (1992–2022) in the Southern part of Kruger National Park and surrounding communities of South Africa. The study estimated the proportion and extent of encroacher plants in relation to native bush species. To achieve this objective, bioclimatic variables, and a digital elevation model in conjunction with the Random Forest model were utilized. Classified satellite imageries achieved an overall accuracy of 72 and 93%, respectively. A gradual increase in bush encroachment was observed from 41,947 hectares (ha) (3.4%) in 1992 to 61,225 ha (10%) in 2022. Additionally, this study observed a decline in the spatial extent of native plant species by 178,163.4 ha, while invasive species have expanded by 44,022.17 ha from 1992 to 2022 wet season. There is a significant increase in the invasive woody species across the years; because the p-value (p < 0.000) is <5% (p < 0.05), the significance level is <5%. The findings of this study offer a significant understanding of the historical patterns of bush encroachment over the past three decades. This information serves as a baseline for formulating strategic and sustainable management approaches to combat bush encroachment and promote effective rangeland preservation in predominantly savannah ecosystems.

The Impact of Climate Change and Climate Variability on the Pastoralist Communities in Moyle District, Somali Regional State, Ethiopia

The Impact of Climate Change and Climate Variability on the Pastoralist Communities in Moyle District, Somali Regional State, Ethiopia

From fast to slow risks: Shifting vulnerabilities of flood-related migration in Lodwar, Kenya

Migration triggered by climate variability or climate change is often a problematic yet nearly unavoidable adaptation measure, particularly due to the increasing severity of natural hazards. How relocation is negotiated, and risks are evaluated at different scales are still poorly understood. We discuss the temporality and complexity of risks, that are experienced and approached through socio-spatial differences of intersectional embodiment (Sultana, 2020). The study is based on two flood-related qualitative case studies in the small semi-arid and rapidly growing town of Lodwar in the poorest county of Kenya, Turkana. We propose the typology of fast and slow risks to understand the different strategies, negotiations, and priorities of different people involved. Due to political abstraction, three main slow risks were not addressed: concerning land, water, and income. Consequently, vulnerabilities deepened and shifted at different scales: along the axes of gender and able-bodiedness as women and particularly widows, ageing, sick, and single mothers were bearing the main hardship; but also, between communities as hazard risks were deliberately shifted onto a politically less affluent community. We argue that in the process of negotiations, people have been actively advocating for, trying to manage, and rethinking their slow risks. They have often been employing slow responses, particularly in the form of waiting and reimagining.

Climate-resilient agriculture for livestock and crop production: Perspectives from smallholder farmers in the Eastern Cape province, South Africa

Objective: The aim of the current study was to investigate the smallholder farmers’ perceptions of climate-resilient agriculture (CRA) on livestock and crop production in the Eastern Cape province, South Africa. Materials and Methods: The data on CRA practices were collected from March 2016 to September 2023 through in-depth discussions using open-ended questionnaires, focus group discussions, and participant observation with 92 purposively selected small-scale farmers in six villages in the Eastern Cape province, South Africa. Results: At least 88.0% of the participants were aware of CRA practices, while 67.4% were adopting them. The need for enhancing the resilience of agricultural activities to cope with climate variability and climate change was ubiquitously perceived, with all participants reporting the contribution of CRA practices towards the livelihood security of several households. Conclusion: Smallholder farmers should consider CRA practices as a valid option to promote and increase agricultural productivity and smallholders’ income while reducing their vulnerability. These findings, therefore, provide important information to policymakers that are required to develop conducive policies, investments, and institutional actions needed for the effective use and adoption of CRA practices.

Characterization of climatic drought in the Souss-Massa watershed (Morocco) using the Standardized Precipitation Index (SPI)

In recent decades, drought has become a significant phenomenon attributed to climate change variability. Its long-term repercussions can lead to substantial agricultural, hydrological, social, and economic consequences. This study uses the Standardized Precipitation Index (SPI) to assess drought in Morocco’s SoussMassa watershed, revealing a significant decline in annual precipitation and highlighting the region’s increased drought susceptibility. Specifically, we analyzed data from five weather stations: Amaghouz (1978-2016), Amsoul (1979-2016), Immerguen (1971-2016), Lamded (1982-2016), and Taroudant (1967-2016) using statistical methods recommended by the World Meteorological Organization (WMO) for annual rainfall records. Additionally, we applied the SPI over a 12-month period to identify dry and wet years. Our analysis reveals alternating dry and wet phases, characterized by an overall decline in annual precipitation.

WITHDRAWN: Trend analysis of the extreme rainfall indices from Lake Tana Sub-Basin of the Upper Blue Nile, Ethiopia

Ethiopia is among the African nations most susceptible to climate change because of its frequent droughts and heavy rainfall. Therefore, hydrological and water management problems require an investigation of regional variability and extreme rainfall patterns. This study analyzed the spatiotemporal trends of extreme rainfall in the Lake Tana Sub-Basin (LTSB) of Ethiopia's Upper Blue Nile Basin (UBNB) between 1981 and 2019. The trend and geographic patterns of ten extreme rainfall indices is evaluated using high-resolution data from Climate Hazards Group InfraRed Precipitation Stations (CHIRPS). We used RClimDex, an R software tool, to analyze the ten severe rainfall indices. The variability of the extreme rain indices was also assessed by applying the standard anomaly index (SAI). The trend analysis shows that the majority of rainfall indices decreased in the majority of station locations. Among the rainfall locations, the decreasing trend was only significant in 40% (CWD), 13.33% (R95p and R99p), and 6.66% (RX1day). In contrast, significant positive patterns were revealed in the incidence of rainfall events of R10mm, PRCPTOT, and CDD, with significant positive trends of 26.66% (R10mm) and 40% (PRCPTOT). Furthermore, a spatial distribution result of extreme rainfall trends reveals considerable variations between stations in spatial distribution. Thus, these findings point to the necessity of creating adaptation and mitigation plans for climate change variability within the sub-basin.

Impact of Climate Change Variables on Thrips Complex in Horticultural Crops and their Management: An Overview

Impact of Climate Change Variables on Thrips Complex in Horticultural Crops and their Management: An Overview