Spatiotemporal Analysis of the Frost Regime in the Iberian Peninsula in the Context of Climate Change (1975–2018)

Climate change is having many effects in the agricultural sector, which are being studied worldwide. Undoubtedly, warmer winters and earlier springs produce changes in frost regimes and severity that will affect the sustainability of agricultural production in the area. The Mediterranean region and the Iberian Peninsula (IP) are among the areas where the greatest impact of climate change is expected. Daily data from 68 weather stations of the IP belonging to the European Climate Assessment and Dataset (1975–2018) were used to conduct a spatiotemporal study of the frost regime. The variables calculated include the probability of three frost types according to their severity, frost day, mean absolute minimum yearly temperature, first frost day, last frost day, and frost-free period. These variables were integrated into a geographic information system, which allowed the graphical visualization of their patterns using of geostatistical interpolation techniques (kriging). Changes in frost variables were investigated using the Mann–Kendall test and Sen’s slope estimator. A general reduction in the number of frosts per year is observed (values between −0.04- and −0.8-day frosts per year), as well as an increase in the mean absolute minimum temperature (values between 0.04 and 0.10 °C per year), with very high significant trends throughout the territory. The reduction in the number of frosts is more pronounced at a higher elevation. Frost dates vary greatly due to the orographic characteristics of the IP. The generalized trend is of a significant delay of the autumn frosts (values between 0.4 and 1.06 days/year), as well as early spring frosts (between −0.429 and −1.29 days/year), and as a consequence a longer frost-free period, all changes were much stronger than those found in other regions of the world. These effects of climate change must be mitigated by modifying species, varieties, and cultivation techniques to guarantee sustainable agriculture.

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Monotonic Trend Analysis of Temperature Series over Mandya City, Karnataka

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.36633 ◽

2021 ◽

Vol 9 (VII) ◽

pp. 1530-1535

Author(s):

Madhusudhan M S

Keyword(s):

Climate Change ◽

Trend Analysis ◽

Agricultural Sector ◽

Kendall Test ◽

Temperature Series ◽

Maximum Temperature ◽

Positive Trend ◽

Significance Level ◽

Monotonic Trend ◽

Indirect Impacts

Climate change is mostly driven by global warming. Climate change is one of the most critical long-term development issues, particularly for developing countries like India. India is one of the world's most climatically diverse countries, making it sensitive to climatic change and impacting the livelihoods of millions of people who rely on agriculture. Temperature and its fluctuation have direct and indirect impacts on crop development in the agricultural sector. Understanding the temperature and its variability in a changing environment would aid in improved decision-making and suggest feasible adaption strategies. The present study focuses on temperature trend analysis in Mandya city, Karnataka, India. The analysis was carried out through the non-parametric Mann-Kendall test and Sen's slope estimator. The findings demonstrate that, there has been a rising trend in temperature in the study area over the last 30 years as a result of climate change. From the analysis, there is a significant positive trend for all the seasons considered for the significance level of 90%, 95% and 99%. The magnitude of the increasing trend will be in the range of 0.46 °C/year for the average time series. Also, there will be an average increase of 0.07 °C/year for the various scenarios considered in Mandya city for the Maximum temperature series.

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Spatiotemporal Characteristics and Trends of Meteorological Droughts in the Wadi Mina Basin, Northwest Algeria

Water ◽

10.3390/w13213103 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3103

Author(s):

Mohammed Achite ◽

Andrzej Wałęga ◽

Abderrezak Kamel Toubal ◽

Hamidi Mansour ◽

Nir Krakauer

Keyword(s):

Agricultural Sector ◽

Standardized Precipitation Index ◽

Kendall Test ◽

Geographical Variations ◽

The People ◽

Slope Estimator ◽

Temporal Dimensions ◽

The Standardized Precipitation Index ◽

Meteorological Droughts ◽

Precipitation Trends

Drought has become a recurrent phenomenon in Algeria in the last few decades. Significant drought conditions were observed during the late 1980s and late 1990s. The agricultural sector and water resources have been under severe constraints from the recurrent droughts. In this study, spatial and temporal dimensions of meteorological droughts in the Wadi Mina basin (4900 km2) were investigated to assess vulnerability. The Standardized Precipitation Index (SPI) method and GIS were used to detail temporal and geographical variations in drought based on monthly records for the period 1970–2010 at 16 rainfall stations located in the Wadi Mina basin. Trends in annual SPI for stations in the basin were analyzed using the Mann–Kendall test and Sen’s slope estimator. Results showed that the SPI was able to detect historical droughts in 1982/83, 1983/84, 1989/90, 1992/93, 1993/94, 1996/97, 1998/99, 1999/00, 2004/05 and 2006/07. Wet years were observed in 1971/72, 1972/73, 1995/96, 2008/09 and 2009/10. Six out of 16 stations had significant decreasing precipitation trends (at 95% confidence), whereas no stations had significant increasing precipitation trends. Based on these findings, measures to ameliorate and mitigate the effects of droughts, especially the dominant intensity types, on the people, community and environment are suggested.

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Trend analysis in reference evapotranspiration and aridity index in the context of climate change in Togo

Journal of Water and Climate Change ◽

10.2166/wcc.2015.111 ◽

2015 ◽

Vol 6 (4) ◽

pp. 848-864 ◽

Cited By ~ 10

Author(s):

Djaman Koffi ◽

Ganyo Komla

Keyword(s):

Climate Change ◽

Reference Evapotranspiration ◽

Aridity Index ◽

Kendall Test ◽

Rainfed Agriculture ◽

Mann Kendall Test ◽

Parametric Statistics ◽

Slope Estimator ◽

Study Sites ◽

Key Parameter

Reference evapotranspiration is a key parameter in hydrological and meteorological studies and used to determine the actual water use rate for various crops. The objectives of this study were to explore trend in the grass-reference evapotranspiration (ETo) through years 1961–2011 and to identify trend in the aridity index as an indicator of change in climate in Togo. ETo was calculated using the FAO-56 Penman–Monteith method, and trends analyses were performed with non-parametric statistics proposed by Mann–Kendall and the Sen slope estimator. Results showed that annual ETo varied from 1,440 to 1,690 mm at Lomé, from 1,761 to 1,905 mm at Tabligbo, and from 1,839 to 1,990 mm at Sokode. The Mann–Kendall test revealed significant increase in annual ETo at Tabligbo (Z = 2.89) and Sokode (Z = 2.29). Annual ETo is much more stable at Lomé, with non-significant decrease. In Togo, according to the three study sites, the 1961–2011 period annual aridity index varied from 0.26 to 0.99 at Lomé, 0.38 to 0.98 at Tabligbo, and 0.45 to 1.08 at Sokode. The Mann–Kendall test revealed a declining trend in the ratio of precipitation/ETo which adversely implies an increasing severity of the aridity index at all the sites, prejudicial to rainfed agriculture practiced by about 90% of Togolese crop growers.

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Trend Detection in Seasonal Inflows and the Influence on Energy Generation in Goleşti Hydropower Plant

The Journal of CIEES ◽

10.48149/jciees.2021.1.1.1 ◽

2021 ◽

Vol 1 (1) ◽

pp. 7-11

Author(s):

A. Neagoe ◽

E.-I. Tică ◽

A. Achim ◽

B. Popa

Keyword(s):

Climate Change ◽

Electricity Generation ◽

Water Cycle ◽

Kendall Test ◽

Hydropower Plant ◽

Trend Detection ◽

Daily Data ◽

Long Term Trends ◽

Water Uses

Among the multiple water uses, electricity generation is a factor strongly affected by alterations in the water cycle due to climate change. Long periods of drought followed by rainy periods lead to significant changes in the natural regimes of water flow in rivers. This paper aims to determine the long-term trends of seasonal inflows (spring, summer, autumn, winter) in Goleşti reservoir using daily data recorded over an 11-years period with the non-parametric Mann-Kendall test. The influence of tendency of increasing or decreasing was analyzed for the inflows in the Goleşti reservoir on the energy produced in associated hydropower plant.

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Climate Change and Variability in the Northeastern Himalayan Region of India

Landscape & Environment ◽

10.21120/le/15/2/5 ◽

2021 ◽

Vol 15 (2) ◽

pp. 53-64

Author(s):

Benjamin L Saitluanga ◽

Gabriel Lalchhandama ◽

P Rinawma

Keyword(s):

Climate Change ◽

Kendall Test ◽

Seasonal Temperature ◽

Rainfall Variation ◽

Mountainous Regions ◽

Climate Change And Variability ◽

Seasonal Temperature Variation ◽

Changing Trend ◽

Change Trend ◽

Slope Estimator

Mountainous regions are considered highly vulnerable to the affects of climate change. The extent of change and variability of climatic parameters is still unexamined in many remote mountainous areas. This paper aims in understanding the change in pattern of rainfall and temperature for a period of 30 years in Mizoram. The analysis of time series changing trend in climatic variables is carried out by using Coefficient of Variation (CV), Mann-Kendall (M-K) and Sen’s Slope estimator. The analysis reveals that high variation is observed for both the variables in all the decadal, three decadal and seasonal change. The CV analysis shows that the highest seasonal rainfall variation occurs during winter and the highest seasonal temperature variation occurs during spring. Mann-Kendall test shows a significant change in rainfall with November showing the highest negative trend of rainfall. The temperature trend analysis in the study also reveals drastic change of temperature. An understanding of climatic change, trend and variability helps in predicting for better natural resources from the susceptibility of climate change.

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DISSEMINATION AND USE OF INFORMATION ON CLIMATE CHANGE AND VARIABILITY: A CASE STUDY OF FARMERS IN MALUGA AND CHIBELA VILLAGES IN SEMI-ARID CENTRAL TANZANIA

Mousaion ◽

10.25159/0027-2639/157 ◽

2016 ◽

Vol 33 (3) ◽

pp. 1-24

Author(s):

Emmanuel Elia ◽

Stephen Mutula ◽

Christine Stilwell

Keyword(s):

Climate Change ◽

Data Collection ◽

Diffusion Of Innovations ◽

Agricultural Development ◽

Agricultural Sector ◽

Policy Framework ◽

Accurate Information ◽

Adaptation To Climate Change ◽

Climate Change And Variability ◽

Semi Arid

This study was part of broader PhD research which investigated how access to, and use of, information enhances adaptation to climate change and variability in the agricultural sector in semi-arid Central Tanzania. The research was carried out in two villages using Rogersâ€™ Diffusion of Innovations theory and model to assess the dissemination of this information and its use by farmers in their adaptation of their farming practices to climate change and variability. This predominantly qualitative study employed a post-positivist paradigm. Some elements of a quantitative approach were also deployed in the data collection and analysis. The principal data collection methods were interviews and focus group discussions. The study population comprised farmers, agricultural extension officers and the Climate Change Adaptation in Africa project manager. Qualitative data were subjected to content analysis whereas quantitative data were analysed to generate mostly descriptive statistics using SPSS. Â Key findings of the study show that farmers perceive a problem in the dissemination and use of climate information for agricultural development. They found access to agricultural inputs to be expensive, unreliable and untimely. To mitigate the adverse effects of climate change and variability on farming effectively, the study recommends the repackaging of current and accurate information on climate change and variability, farmer education and training, and collaboration between researchers, meteorology experts, and extension officers and farmers. Moreover, a clear policy framework for disseminating information related to climate change and variability is required.

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Impact of air–sea coupling on the climate change signal over the Iberian Peninsula

Climate Dynamics ◽

10.1007/s00382-021-05812-x ◽

2021 ◽

Author(s):

Alba de la Vara ◽

William Cabos ◽

Dmitry V. Sein ◽

Claas Teichmann ◽

Daniela Jacob

Keyword(s):

Climate Change ◽

Iberian Peninsula ◽

Mediterranean Sea ◽

Large Scale ◽

Regional Distribution ◽

Coupled Model ◽

Climate Change Signal ◽

The North ◽

The Mediterranean ◽

The Impact

AbstractIn this work we use a regional atmosphere–ocean coupled model (RAOCM) and its stand-alone atmospheric component to gain insight into the impact of atmosphere–ocean coupling on the climate change signal over the Iberian Peninsula (IP). The IP climate is influenced by both the Atlantic Ocean and the Mediterranean sea. Complex interactions with the orography take place there and high-resolution models are required to realistically reproduce its current and future climate. We find that under the RCP8.5 scenario, the generalized 2-m air temperature (T2M) increase by the end of the twenty-first century (2070–2099) in the atmospheric-only simulation is tempered by the coupling. The impact of coupling is specially seen in summer, when the warming is stronger. Precipitation shows regionally-dependent changes in winter, whilst a drier climate is found in summer. The coupling generally reduces the magnitude of the changes. Differences in T2M and precipitation between the coupled and uncoupled simulations are caused by changes in the Atlantic large-scale circulation and in the Mediterranean Sea. Additionally, the differences in projected changes of T2M and precipitation with the RAOCM under the RCP8.5 and RCP4.5 scenarios are tackled. Results show that in winter and summer T2M increases less and precipitation changes are of a smaller magnitude with the RCP4.5. Whilst in summer changes present a similar regional distribution in both runs, in winter there are some differences in the NW of the IP due to differences in the North Atlantic circulation. The differences in the climate change signal from the RAOCM and the driving Global Coupled Model show that regionalization has an effect in terms of higher resolution over the land and ocean.

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The impact of climate change in wheat and barley yields in the Iberian Peninsula

Scientific Reports ◽

10.1038/s41598-021-95014-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Virgílio A. Bento ◽

Andreia F. S. Ribeiro ◽

Ana Russo ◽

Célia M. Gouveia ◽

Rita M. Cardoso ◽

...

Keyword(s):

Climate Change ◽

Iberian Peninsula ◽

Climate Model ◽

Global Climate Models ◽

Maximum Temperature ◽

Historical Period ◽

Early Winter ◽

Impact Of Climate Change ◽

The Impact ◽

Spring Maximum

AbstractThe impact of climate change on wheat and barley yields in two regions of the Iberian Peninsula is here examined. Regression models are developed by using EURO-CORDEX regional climate model (RCM) simulations, forced by ERA-Interim, with monthly maximum and minimum air temperatures and monthly accumulated precipitation as predictors. Additionally, RCM simulations forced by different global climate models for the historical period (1972–2000) and mid-of-century (2042–2070; under the two emission scenarios RCP4.5 and RCP8.5) are analysed. Results point to different regional responses of wheat and barley. In the southernmost regions, results indicate that the main yield driver is spring maximum temperature, while further north a larger dependence on spring precipitation and early winter maximum temperature is observed. Climate change seems to induce severe yield losses in the southern region, mainly due to an increase in spring maximum temperature. On the contrary, a yield increase is projected in the northern regions, with the main driver being early winter warming that stimulates earlier growth. These results warn on the need to implement sustainable agriculture policies, and on the necessity of regional adaptation strategies.

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Testing Possible Scenario-Based Responses of Vegetation Under Expected Climatic Changes in Khuzestan Province

Air Soil and Water Research ◽

10.1177/11786221211013332 ◽

2021 ◽

Vol 14 ◽

pp. 117862212110133

Author(s):

Hadi Eskandari Damaneh ◽

Meysam Jafari ◽

Hamed Eskandari Damaneh ◽

Marjan Behnia ◽

Asadollah Khoorani ◽

...

Keyword(s):

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Kendall Test ◽

Baseline Period ◽

System Model ◽

Future Period ◽

Khuzestan Province ◽

Ecosystem Planning ◽

Slope Estimator ◽

Precipitation And Temperature

Projections of future scenarios are scarce in developing countries where human activities are increasing and impacting land uses. We present a research based on the assessment of the baseline trends of normalized difference vegetation index (NDVI), precipitation, and temperature data for the Khuzestan Province, Iran, from 1984 to 2015 compiled from ground-based and remotely sensed sources. To achieve this goal, the Sen’s slope estimator, the Mann-Kendall test, and Pearson’s correlation test were used. After that, future trends in precipitation and temperature were estimated using the Canadian Earth System Model (CanESM2) model and were then used to estimate the NDVI trend for two future periods: from 2016 to 2046 and from 2046 to 2075. Our results showed that during the baseline period, precipitation decreased at all stations: 33.3% displayed a significant trend and the others were insignificant ones. Over the same period, the temperature increased at 66.7% of stations while NDVI decreased at all stations. The NDVI–precipitation relationship was positive while NDVI–temperature showed an inverse trend. During the first of the possible future periods and under the RCP2.6, RCP4.5, and RCP8.5 scenarios, NDVI and precipitation decreased, and temperatures significantly increased. In addition, the same trends were observed during the second future period; most of these were statistically significant. We conclude that much assessments are valuable and integral components of effective ecosystem planning and decisions.

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Calcium and Potassium Nutrition Increases the Water Use Efficiency in Coffee: A Promising Strategy to Adapt to Climate Change

Hydrology ◽

10.3390/hydrology8020075 ◽

2021 ◽

Vol 8 (2) ◽

pp. 75

Author(s):

Victor Hugo Ramírez-Builes ◽

Jürgen Küsters

Keyword(s):

Climate Change ◽

Climate Variability ◽

Water Use Efficiency ◽

Water Use ◽

Agricultural Sector ◽

Regional Scale ◽

Adaptation Strategies ◽

Caribbean Region ◽

Coffee Production ◽

Use Efficiency

Coffee (Coffea spp.) represents one of the most important sources of income and goods for the agricultural sector in Central America, Colombia, and the Caribbean region. The sustainability of coffee production at the global and regional scale is under threat by climate change, with a major risk of losing near to 50% of today’s suitable area for coffee by 2050. Rain-fed coffee production dominates in the region, and under increasing climate variability and climate change impacts, these production areas are under threat due to air temperature increase and changes in rainfall patterns and volumes. Identification, evaluation, and implementation of adaptation strategies for growers to cope with climate variability and change impacts are relevant and high priority. Incremental adaptation strategies, including proper soil and water management, contribute to improved water use efficiency (WUE) and should be the first line of action to adapt the coffee crop to the changing growing conditions. This research’s objective was to evaluate at field level over five years the influence of fertilization with calcium (Ca+2) and potassium (K+) on WUE in two coffee arabica varieties: cv. Castillo and cv. Caturra. Castillo has resistance against coffee leaf rust (CLR) (Hemileia vastatrix Verkeley and Brome), while Caturra is not CLR-resistant. WUE was influenced by yield changes during the years by climate variability due to El Niño–ENSO conditions and CLR incidence. Application of Ca+2 and K+ improved the WUE under such variable conditions. The highest WUE values were obtained with an application of 100 kg CaO ha−1 year−1 and between 180 to 230 kg K2O ha−1 year−1. The results indicate that adequate nutrition with Ca+2 and K+ can improve WUE in the long-term, even underwater deficit conditions and after the substantial incidence. Hence, an optimum application of Ca+2 and K+ in rain-fed coffee plantations can be regarded as an effective strategy to adapt to climate variability and climate change.

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