Hydro-Meteorological Trends in an Austrian Low-Mountain Catchment

While ongoing climate change is well documented, the impacts exhibit a substantial variability, both in direction and magnitude, visible even at regional and local scales. However, the knowledge of regional impacts is crucial for the design of mitigation and adaptation measures, particularly when changes in the hydrological cycle are concerned. In this paper, we present hydro-meteorological trends based on observations from a hydrological research basin in Eastern Austria between 1979 and 2019. The analyzed variables include air temperature, precipitation, and catchment runoff. Additionally, the number of wet days, trends for catchment evapotranspiration, and computed potential evapotranspiration were derived. Long-term trends were computed using a non-parametric Mann–Kendall test. The analysis shows that while mean annual temperatures were decreasing and annual temperature minima remained constant, annual maxima were rising. Long-term trends indicate a shift of precipitation to the summer, with minor variations observed for the remaining seasons and at an annual scale. Observed precipitation intensities mainly increased in spring and summer between 1979 and 2019. Catchment actual evapotranspiration, computed based on catchment precipitation and outflow, showed no significant trend for the observed time period, while potential evapotranspiration rates based on remote sensing data increased between 1981 and 2019.

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Hydro-Meteorological Trends in an Austrian Low-Mountain Catchment

10.20944/preprints202106.0104.v1 ◽

2021 ◽

Author(s):

Gerald Krebs ◽

David Camhy ◽

Dirk Muschalla

Keyword(s):

Hydrological Cycle ◽

Mean Annual Temperature ◽

State Variables ◽

Adaptation Measures ◽

Mitigation And Adaptation ◽

Regional Impacts ◽

Time Period ◽

Mountain Catchment ◽

Long Term Trends ◽

Annual Scale

While the ongoing climate change is well documented, the impacts exhibit a substantial variability, both in direction and magnitude, visible even at regional and local scales. However, the knowledge of regional impacts is crucial for the design of mitigation and adaptation measures, particularly when changes in the hydrological cycle are concerned. In this paper we present hydro-meteorological trends based on observations from a hydrological research basin in Eastern Austria between 1979-2019. The analysed state variables include the air temperature, the precipitation, and the catchment runoff. Additionally, trends for the catchment evapotranspiration were derived. The analysis shows that while the mean annual temperature was decreasing and annual temperature minima remained constant, the annual maxima were rising. The long-term trends indicate a shift of precipitation to the summer with minor variations observed for the remaining seasons and at an annual scale. Observed precipitation intensities mainly increased in spring and summer between 1979-2019. The catchment evapotranspiration, computed based on catchment precipitation and outflow, showed an increasing trend for the observed time period.

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Recent Climate Change in the Lake Kyoga Basin, Uganda: An Analysis Using Short-Term and Long-Term Data with Standardized Precipitation and Anomaly Indexes

Climate ◽

10.3390/cli9120179 ◽

2021 ◽

Vol 9 (12) ◽

pp. 179

Author(s):

John Peter Obubu ◽

Seyoum Mengistou ◽

Tadesse Fetahi ◽

Tena Alamirew ◽

Robinson Odong ◽

...

Keyword(s):

Climate Change ◽

Kendall Test ◽

Rainfall Anomaly ◽

Short Term ◽

Adaptation Measures ◽

Mitigation And Adaptation ◽

Weather Events ◽

Recent Climate ◽

Term Data

Climate change (CC) is now a global challenge due to uncertainties on the drivers and the multifaceted nature of its impacts. It impacts many sectors such as agriculture, water supply, and global economies through temperature and precipitation, affecting many livelihoods. Although there are global, regional, and national studies on CC, their application to determine local CC occurence mitigation and adaptation measures is not ideal. Therefore, this study aimed to determine climate change trends in Lake Kyoga Basin using standardized precipitation and anomaly indexes. Short-term (39 years, 1981–2020) and long-term (59 years, 1961–2020) monthly data from eight strategic meteorological stations were acquired from the Uganda National Meteorological Authority and supplemented with satellite and model reanalysis climate datasets. Change in precipitation was determined by SPI-6, while SAI determined change in temperature. The Mann–Kendall test was used to determine the trend significance. Whereas two (Serere and Lira) long-term data stations showed significant changes in precipitation, all the short-term data stations showed a significant increasing trend. Decadal relative rainfall anomaly increased from 85.6–105 in 1981–1990 to 92.0–120.9 in 2011–2020, while mean temperature anomaly increased from 0.2–0.6 °C to 1.0–1.6 °C in the same period. The frequency of severe wet weather events was more than for dry weather events in many stations, indicating an increase in precipitation. Maximum, mean, and minimum temperatures increased, with resultant warmer nights. The findings showed that the Lake Kyoga basin is experiencing climate change, with both temperature and rainfall increasing spatially and temporarily. Climate change affects agriculture, which is the main economic activity, and causes the destruction of infrastructure from floods, landslides, and mudslides. The results of this study are helpful in pointing out climate change-affected areas, and hence for designing mitigation and adaption strategies for local communities by policy and decision-makers from relevant stakeholders.

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Analysis of Long-Term Trends of Annual and Seasonal Rainfall in the Awash River Basin, Ethiopia

Water ◽

10.3390/w11071498 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1498 ◽

Cited By ~ 2

Author(s):

Solomon Mulugeta ◽

Clifford Fedler ◽

Mekonen Ayana

Keyword(s):

Climate Change ◽

River Basin ◽

Summer Rainfall ◽

Seasonal Rainfall ◽

Winter Rainfall ◽

Adaptation Measures ◽

Awash River Basin ◽

Long Term Trends ◽

Increasing Trends

With climate change prevailing around the world, understanding the changes in long-term annual and seasonal rainfall at local scales is very important in planning for required adaptation measures. This is especially true for areas such as the Awash River basin where there is very high dependence on rain- fed agriculture characterized by frequent droughts and subsequent famines. The aim of the study is to analyze long-term trends of annual and seasonal rainfall in the Awash River Basin, Ethiopia. Monthly rainfall data extracted from Climatic Research Unit (CRU 4.01) dataset for 54 grid points representing the entire basin were aggregated to find the respective areal annual and seasonal rainfall time series for the entire basin and its seven sub-basins. The Mann-Kendall (MK) test and Sen Slope estimator were applied to the time series for detecting the trends and for estimating the rate of change, respectively. The Statistical software package R version 3.5.2 was used for data extraction, data analyses, and plotting. Geographic information system (GIS) package was also used for grid making, site selection, and mapping. The results showed that no significant trend (at α = 0.05) was identified in annual rainfall in all sub-basins and over the entire basin in the period (1902 to 2016). However, the results for seasonal rainfall are mixed across the study areas. The summer rainfall (June through September) showed significant decreasing trend (at α ≤ 0.1) over five of the seven sub-basins at a rate varying from 4 to 7.4 mm per decade but it showed no trend over the two sub-basins. The autumn rainfall (October through January) showed no significant trends over four of the seven sub-basins but showed increasing trends over three sub-basins at a rate varying from 2 to 5 mm per decade. The winter rainfall (February through May) showed no significant trends over four sub-basins but showed significant increasing trends (at α ≤ 0.1) over three sub-basins at a rate varying from 0.6 to 2.7 mm per decade. At the basin level, the summer rainfall showed a significant decreasing trend (at α = 0.05) while the autumn and winter rainfall showed no significant trends. In addition, shift in some amount of summer rainfall to winter and autumn season was noticed. It is evident that climate change has shown pronounced effects on the trends and patterns of seasonal rainfall. Thus, the study contribute to better understanding of climate change in the basin and the information from the study can be used in planning for adaptation measures against a changing climate.

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Long-Term Trends of Air Pollution at National Atmospheric Observatory Košetice (ACTRIS, EMEP, GAW)

Atmosphere ◽

10.3390/atmos11050537 ◽

2020 ◽

Vol 11 (5) ◽

pp. 537

Author(s):

Milan Váňa ◽

Adéla Holubová Smejkalová ◽

Jaroslava Svobodová ◽

Pavel Machálek

Keyword(s):

Czech Republic ◽

Air Quality ◽

Kendall Test ◽

Significant Drop ◽

The Czech Republic ◽

Pollution Levels ◽

Volatile Organic ◽

International Projects ◽

Long Term Trends

The National Atmospheric Observatory Košetice operated by the Czech Hydrometeorological Institute was established in 1988 as a station specializing in air quality monitoring at the background scale. The observatory is located in the free area outside of the settlement and represents the Czech Republic in various international projects. The objective of the present study is to detect the long-term trends of air quality at the background scale of the Czech Republic. The statistical method used for trend analysis is based on the nonparametric Mann–Kendall test. Generally, the results show that the fundamental drop in emission of basic air pollutants was reflected in the significant decrease in pollution levels. A most significant drop was detected for sulphur. No trend was found for NO2 in 1990–2012, but a visibly decreasing tendency was registered in the last 7 years. A slightly decreasing trend was registered for O3 in the whole period, but a slightly increasing tendency was found after 2006. More importantly, the number of episodes exceeding the target value for human health dropped significantly. The reduction of volatile organic compounds (VOCs) emissions was reflected in a statistically significant decrease of concentrations. Only isoprene, which is of natural origin, displays an inverse trend. Concentrations of elemental carbon (EC) and organic carbon (OC) dropped since 2010, but only for EC is the trend statistically significant.

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Long Term Historic Changes in the Flow of Lesser Zab River, Iraq

Hydrology ◽

10.3390/hydrology6010022 ◽

2019 ◽

Vol 6 (1) ◽

pp. 22 ◽

Cited By ~ 8

Author(s):

Rawshan Ali ◽

Arez Ismael ◽

Arien Heryansyah ◽

Nadeem Nawaz

Keyword(s):

Climate Change ◽

Scientific Community ◽

River Flow ◽

Kendall Test ◽

Hydraulic Structures ◽

Trend Test ◽

Adaptation Measures ◽

Sen’S Slope ◽

Water Scarce

The assessment of trends in river flows has become of interest to the scientific community in order to understand the changing characteristics of flow due to climate change. In this study, the trends in river flow of Dukan Dam located in the northern part of Iraq were assessed. The assessment was carried out for the period 1964 to 2013 using Sen’s slope and the Mann–Kendall test. Sen’s slope was used to assess the magnitude of change while the Mann–Kendall trend test was used to confirm the significance of trends. The results of the study showed that there was a decreasing trend in river flow both annually and for all individual months. The highest decreasing trend of −5.08846 m3/month was noticed in April, while the lowest change of −1.06022 m3/month was noticed in November. The annual flow also showed a significant decrease at a rate of −1.912 m3/year at a 95% level of confidence. Additionally, the findings of the study also confirmed that a decrease in precipitation and the construction of hydraulic structures reduced the flow in the river. The findings of the study suggest that decreasing trends may cause a water-scarce situation in the future if proper adaptation measures are not taken.

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Long-Term Trends in 20-Day Cumulative Precipitation for Residential Rainwater Harvesting in Poland

Water ◽

10.3390/w12071932 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1932 ◽

Cited By ~ 2

Author(s):

Fausto A. Canales ◽

Joanna Gwoździej-Mazur ◽

Piotr Jadwiszczak ◽

Joanna Struk-Sokołowska ◽

Katarzyna Wartalska ◽

...

Keyword(s):

Time Series ◽

Water Conservation ◽

Rainwater Harvesting ◽

Kendall Test ◽

Integrated Water Management ◽

Operation Conditions ◽

Long Time ◽

Long Term Trends ◽

Availability Index

Rainwater harvesting (RWH) for domestic uses is widely regarded as an economic and ecological solution in water conservation and storm management programs. This paper aims at evaluating long-term trends in 20-day cumulative rainfall periods per year in Poland, for assessing its impact on the design and operation conditions for RWH systems and resource availability. The time-series employed corresponds to a set of 50-year long time-series of rainfall (from 1970 to 2019) recorded at 19 synoptic meteorological stations scattered across Poland, one of the European countries with the lowest water availability index. The methods employed for assessing trends were the Mann–Kendall test (M–K) and the Sen’s slope estimator. Most of the datasets exhibit stationary behaviour during the 50-year long period, however, statistically significant downward trends were detected for precipitations in Wrocław and Opole. The findings of this study are valuable assets for integrated water management and sustainable planning in Poland.

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Adaptation to Global-Warming-Triggered Water Disasters Measures Taken by Science Council of Japan

Journal of Disaster Research ◽

10.20965/jdr.2009.p0003 ◽

2009 ◽

Vol 4 (1) ◽

pp. 3-6

Author(s):

Syunsuke Ikeda ◽

◽

Keyword(s):

Climate Change ◽

Paradigm Shift ◽

Global Climate ◽

Social Changes ◽

Development Programs ◽

Adaptation Measures ◽

Mitigation And Adaptation ◽

The Social ◽

The Government

As pointed out by Assessment Report 4 of IPCC, global climate change will increase the magnitude and frequency of water-related disasters such as flooding, surge and drought. In addition to this the social changes such as population problems in Japan will aggravate the vulnerability to the disasters. Two concepts to cope with the water-related disasters triggered by climate change are adaptation and mitigation. Though abatement of GHG gas emissions has been eagerly argued, Japan should be more concerned with and take the initiative both for mitigation and adaptation. As adaptation measures for water-related disasters, 3 measures are proposed in this paper; building disaster-awareness societies, building physical/social structures, and adaptation R&D. In addition to them, it is necessary to bring reconstruction of the national land into medium- and long term views as paradigm shift. In this paper, the following recommendations are proposed for the adaptation: the Japanese government should be aware of the importance of adaptation and strongly promote adaptation to mitigate water-related disasters, and the government should also cooperate in establishing adaptation in sustaining development of Asian monsoon areas and development programs.

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Closing the water cycle from observations across scales: Where do we stand?

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-19-0316.1 ◽

2021 ◽

pp. 1-95

Author(s):

Wouter Dorigo ◽

Stephan Dietrich ◽

Filipe Aires ◽

Luca Brocca ◽

Sarah Carter ◽

...

Keyword(s):

Hydrological Cycle ◽

Water Cycle ◽

Global Climate ◽

Spatial Scales ◽

Spatial And Temporal Scales ◽

Mitigation And Adaptation ◽

Consistent Assessment ◽

Earth’S Climate ◽

Improved Model

AbstractLife on Earth vitally depends on the availability of water. Human pressure on freshwater resources is increasing, as is human exposure to weather-related extremes (droughts, storms, floods) caused by climate change. Understanding these changes is pivotal for developing mitigation and adaptation strategies. The Global Climate Observing System (GCOS) defines a suite of Essential Climate Variables (ECVs), many related to the water cycle, required to systematically monitor the Earth's climate system. Since long-term observations of these ECVs are derived from different observation techniques, platforms, instruments, and retrieval algorithms, they often lack the accuracy, completeness, resolution, to consistently to characterize water cycle variability at multiple spatial and temporal scales.Here, we review the capability of ground-based and remotely sensed observations of water cycle ECVs to consistently observe the hydrological cycle. We evaluate the relevant land, atmosphere, and ocean water storages and the fluxes between them, including anthropogenic water use. Particularly, we assess how well they close on multiple temporal and spatial scales. On this basis, we discuss gaps in observation systems and formulate guidelines for future water cycle observation strategies. We conclude that, while long-term water-cycle monitoring has greatly advanced in the past, many observational gaps still need to be overcome to close the water budget and enable a comprehensive and consistent assessment across scales. Trends in water cycle components can only be observed with great uncertainty, mainly due to insufficient length and homogeneity. An advanced closure of the water cycle requires improved model-data synthesis capabilities, particularly at regional to local scales.

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Long-term changes in rice development in Southern Brazil, during the last ten decades

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2012000600001 ◽

2012 ◽

Vol 47 (6) ◽

pp. 727-737 ◽

Cited By ~ 1

Author(s):

Nereu Augusto Streck ◽

Lilian Osmari Uhlmann ◽

Luana Fernandes Gabriel

Keyword(s):

Kendall Test ◽

Maximum Daily Temperature ◽

Developmental Models ◽

Time Period ◽

Long Term Trends ◽

Emergence Date ◽

Leaf Appearance ◽

Santa Maria ◽

Rice Phenology

The objective of this work was to test long-term trends in the duration of rice development phases in Santa Maria, RS, Brazil. The duration from emergence to V3 (EM-V3), emergence to panicle differentiation (EM-R1), emergence to anthesis (EM-R4), and emergence to all grains with brown hull (EM-R9) was calculated using leaf appearance and developmental models for four rice cultivars (IRGA 421, IRGA 417, EPAGRI 109, and EEA 406), for the period from 1912 to 2011, considering three emergence dates (early, mid, and late). The trend of the time series was tested with the non-parametric Mann-Kendall test, and the magnitude of the trend was estimated with simple linear regression. Rice development has changed over the last ten decades in this location, leading to an anticipation of harvest time of 17 to 31 days, depending on the cultivar maturity group and emergence date, which is related to trends of temperature increase during the growing season. Warmer temperatures over the evaluated time period are responsible for changing rice phenology in this location, since minimum and maximum daily temperature drive the rice developmental models used.

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Probabilities of Causation of Climate Changes

Journal of Climate ◽

10.1175/jcli-d-17-0304.1 ◽

2018 ◽

Vol 31 (14) ◽

pp. 5507-5524 ◽

Cited By ~ 3

Author(s):

Alexis Hannart ◽

Philippe Naveau

Keyword(s):

Climate Changes ◽

The Past ◽

Detection And Attribution ◽

Mitigation And Adaptation ◽

Event Attribution ◽

Long Term Trends ◽

Earth’S Climate ◽

Anthropogenic Forcings ◽

Event Occurrence

Multiple changes in Earth’s climate system have been observed over the past decades. Determining how likely each of these changes is to have been caused by human influence is important for decision making with regard to mitigation and adaptation policy. Here we describe an approach for deriving the probability that anthropogenic forcings have caused a given observed change. The proposed approach is anchored into causal counterfactual theory ( Pearl 2009 ), which was introduced recently, and in fact partly used already, in the context of extreme weather event attribution (EA). We argue that these concepts are also relevant to, and can be straightforwardly extended to, the context of detection and attribution of long-term trends associated with climate change (D&A). For this purpose, and in agreement with the principle of fingerprinting applied in the conventional D&A framework, a trajectory of change is converted into an event occurrence defined by maximizing the causal evidence associated to the forcing under scrutiny. Other key assumptions used in the conventional D&A framework, in particular those related to numerical model error, can also be adapted conveniently to this approach. Our proposal thus allows us to bridge the conventional framework with the standard causal theory, in an attempt to improve the quantification of causal probabilities. An illustration suggests that our approach is prone to yield a significantly higher estimate of the probability that anthropogenic forcings have caused the observed temperature change, thus supporting more assertive causal claims.

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