WATER EXCHANGES: TOOLS TO BEAT EL NIÑO CLIMATE VARIABILITY IN IRRIGATED AGRICULTURE1

ABSTRACT: Using a case study of the Yakima River Valley in Washington State, this paper shows that relatively simple tools can be used to forecast the impact of the El Niño phenomenon on water supplies to irrigated agriculture, that this information could be used to estimate the significantly shifted probability distribution of water shortages in irrigated agriculture during El Niño episodes, and that these shifted probabilities can be used to estimate the value of exchanges of water between crops to relieve some of the adverse consequences of such shortages under western water law. Further, recently devised water‐trading tools, while not completely free under western water law to respond to forecasted El Niño episodes (ocean circulation patterns), are currently being employed during declared drought to reduce the devastating effects of water shortages in junior water districts on high valued perennial crops. Additional institutional flexibility is needed to take full advantage of climate forecasting, but even current tools clearly could prove useful in controlling the effects of climate variability in irrigated agriculture. Analysis shows the significant benefit of temporarily transferring or renting water rights from low‐value to high‐value crops, based on El Niño forecasts.     

森林火灾重灾时段对太阳活动,厄尔尼诺,南方涛动异常的响应

本文根据天地生相互作用原理,研究了黑龙江近40多年来森林火灾灾情年际变化规律,发现森林火灾重灾时段(年)与太阳活动谷年及其次年基本同步,与ENSO密切相关;三者是形成“重灾时段”的重大天地生原因。     

Variability and predictability of sea-level extremes in the Hawaiian and U.S.-Trust Islands—a knowledge base for coastal hazards management

The objective of this study is to provide an improved climatology of sea level extremes on seasonal and long-term time scales for Hawaii and the U.S-Trust islands. Observations revealed that the Hawaiian and U.S.-Trust islands, by and large, display a strong annual cycle. For estimating the statistics of return period, the three-parameter generalized extreme value (GEV) distribution is fitted using the method of L-moments. In the context of extremes (20- to 100-year return periods), the deviations in most of the Hawaiian Islands (except at Nawiliwili and Hilo) displayed a moderate sea-level rise (i.e., close to 200 mm), but the deviations in the U.S.-Trust islands displayed a considerably higher rise (i.e., more than 300 mm) in some seasons due to typhoon-related storm surges. This rise may cause damage to roads, harbors, and unstable sandy beaches. Correlations between the El Niño-Southern Oscillation (ENSO) climate cycle and the variability of seasonal sea level have been investigated. Results show that correlation for the station located west of the International Date Line (DL) is strong, but it is moderate or even weaker for stations east of the DL. The skill of SST-based Canonical Correlation Analyses (CCA) forecasts was found to be weak to moderate (0.4–0.6 for Honolulu, Kahului, Hilo, and Wake, and 0.3 or below for Kahului, Mokuoloe, and Johnston). Finally, these findings are synthesized for evaluating the potential implications of sea level variability in these islands.     

Improving Community-Based Conservation Near Protected Areas: The Importance of Development Variables

Community-based conservation projects implemented in conjunction with protected area management often struggle to meet expectations. This article argues that outcomes will improve if project leaders pay closer attention to four development indicators—rights, capacity, governance, and revenue—that are often taken for granted or considered beyond the scope of local conservation projects. I make the case for focusing on these variables in four steps. First, I distinguish community-based conservation linked to protected area management from community-based institutions studied by scholars of the commons. Second, I draw on the theory and practice of international development to highlight the central relevance of the variables highlighted in this article to development projects at all levels. Third, I discuss the four variables in some detail, considering problems of definition and measurement and reviewing possible interactions among them. Fourth, to illustrate the influence of the variables in particular cases, I review outcomes from community-based conservation projects implemented near protected areas in El Salvador and Zimbabwe.     

Institutional, policy and farmer responses to drought: El Niño events and rice in the Philippines

Droughts are common recurring natural hazards in Asia, and El Niño events are particularly severe in the Philippines. This paper explores responses by farm households, irrigation system managers, and macro policymakers in the Philippines to El Niño. In response to the large 1997–98 El Niño, farmers in one major irrigation system significantly diversified their economic activities, hut the drought was so acute that many of these activities were not successful. Communication between meteorologists and irrigation system managers is strong, and irrigation system managers are aware of El Niño events in advance. Communication between irrigation system managers and farmer irrigation associations is also strong, and together they have developed response options that attempt to augment supplies of and more efficiently allocate scarce water. Water pricing is not used, however, and lack of cooperation among farmers results in sub-optimal outcomes. Macro-level policy responses in terms of rice imports and buffer stock management to protect poor consumers have improved substantially over time.     

洪泽湖流域洪涝灾害演变趋势及其与El Ni(n)o事件关系

为分析洪泽湖流域洪涝灾害在千年尺度序列上的演变趋势,采用统计历史洪涝记录的方法,分析了气候变化背景下洪涝灾害的响应过程,探讨了洪泽湖流域洪涝灾害同El Ni(n)o事件的关系.结果表明:近1 000 a来洪泽湖流域洪涝灾害的频度总体是趋于上升的,这种变化趋势同气候变化的趋势是一致的.研究结果显示:公元1000～1400年洪涝记录偏少,同我国东部地区尤其是中世纪暖期出现的一次200 a以上的干旱化过程有较好的对应性.1400～1800年是洪泽湖流域洪涝的多发期,这一事实同我国东部1550～1850年小冰期期间总体偏湿的环境特征相一致.分析洪涝灾害变化同El Ni(n)o事件对应性关系表明:在El Ni(n)o事件年及其次年是洪泽湖流域洪涝的多发年份.这可能是由于El Ni(n)o事件通过改变西太平洋副高的强度与位置,以及大气环流形势而引起的降水异常所致.了解洪泽湖流域洪涝的演变趋势及其同El Ni(n)o的关系对于长期防灾减灾策略具有重要的参考意义.     

Natural radionuclides distribution and environmental impacts of ferruginous sand-siltstone (raw material) and their manufactured Ahmer oxide used as wall paints

Commercially known Ahmer oxide paints are prepared from raw material mainly composed of red iron oxides (hematite) and iron oxyhydroxides. The raw material used in manufacturing of Ahmer oxide comes from some localities in southwest Sinai such as Abu Thor, Allouga, and El lehian. The adsorption of uranium and other radioelements on iron oxides could make the raw material (red iron oxides) and their products environmentally hazardous. The studied samples were subjected to radiometric analysis using NaI (Tl) gamma-ray spectrometer. The average activity concentration of U, Th, Ra, and K are 108.7, 458.8, 88.8, and 627.5?Bq?kg^?1, respectively in raw material and 136.4, 14.6, 58.3, and 95.9?Bq?kg^?1 in Ahmer oxide. High values of activity concentrations of ²³⁸U, ²²⁶Ra, and ⁴⁰K were recorded in Allouga and El lehian raw material. High radioactivities of Allouga and El lehian raw material are mainly attributed to the presence of torbernite, zircon, and monazite, in addition to adsorbed elemental uranium in Ahmer oxide. absorbed dose rate (D), annual effective dose equivalent, radium equivalent activity (Ra_eq), external hazard index (H_ex), and internal hazard index (H_in), as well as representative gamma index (Iγ) were determined from the activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K. Some of the studied samples do not satisfy the universal standards.     

Evaluation of the influence of El Niño–Southern Oscillation on air quality in southern China from long-term historical observations

•Strong ENSO influence on AOD is found in southern China region. •Low AOD occurs in El Niño but high AOD occurs in La Niña events in southern China. •Angstrom exponent anomalies reveals the circulation pattern during each ENSO phase. •ENSO exerts large influence (70.5%) on annual variations of AOD during 2002–2020. •Change of anthropogenic emissions is the dominant driver for AOD trend (2002–2020). Previous studies demonstrated that the El Niño–Southern Oscillation (ENSO) could modulate regional climate thus influencing air quality in the low-middle latitude regions like southern China. However, such influence has not been well evaluated at a long-term historical scale. To filling the gap, this study investigated two-decade (2002 to 2020) aerosol concentration and particle size in southern China during the whole dynamic development of ENSO phases. Results suggest strong positive correlations between aerosol optical depth (AOD) and ENSO phases, as low AOD occurred during El Niño while high AOD occurred during La Niña event. Such correlations are mainly attributed to the variation of atmospheric circulation and precipitation during corresponding ENSO phase. Analysis of the angstrom exponent (AE) anomalies further confirmed the circulation pattern, as negative AE anomalies is pronounced in El Niño indicating the enhanced transport of sea salt aerosols from the South China Sea, while the La Niña event exhibits positive AE anomalies which can be attributed to the enhanced import of northern fine anthropogenic aerosols. This study further quantified the AOD variation attributed to changes in ENSO phases and anthropogenic emissions. Results suggest that the long-term AOD variation from 2002 to 2020 in southern China is mostly driven (by 64.2%) by the change of anthropogenic emissions from 2002 to 2020. However, the ENSO presents dominant influence (70.5%) on year-to-year variations of AOD during 2002–2020, implying the importance of ENSO on varying aerosol concentration in a short-term period.     

金华旱涝趋势统计分析

根据对旱涝自身变化及其与太阳黑子活动，厄尔尼诺事件关系的分析，，得出了金华旱涝趋势的几点认识：（1）在未来的十几年之内，金华站将从涝年占优势的阶段转入旱年占优势的阶段；（2）在太阳黑子活动22年的磁周期转变年前后，金华站3年平均年降水量明显偏多；（3）在春季型厄尔尼诺事件的当年和夏季型厄尔尼诺事件的次年，金华站年降水量偏多；（4）厄尔尼诺事件的结束时间若超过5月1日，那么次年金华站年降水量偏多；（5）厄尔尼诺事件的强度越大，对金华站年降水量的影响也越大；（6）在太阳黑子活动22年磁周期转变年前后的厄尔尼诺事件的次年，金华站年降水量明显偏多。这些认识对长期及超长期的旱涝趋势预测具有重要的现实意义。     

Multiple impact pathways of the 2015–2016 El Niño in coastal Kenya

The 2015–2016 El Niño had large impacts globally. The effects were not as great as anticipated in Kenya, however, leading some commentators to call it a ‘non-event’. Our study uses a novel combination of participatory Climate Vulnerability and Capacity Analysis tools, and new and existing social and biophysical data, to analyse vulnerability to, and the multidimensional impacts of, the 2015–2016 El Niño episode in southern coastal Kenya. Using a social-ecological systems lens and a unique dataset, our study reveals impacts overlooked by conventional analysis. We show how El Niño stressors interact with and amplify existing vulnerabilities to differentially impact local ecosystems and people. The policy significance of this finding is that the development of specific national capacities to deal with El Niño events is insufficient; it will be necessary to also address local vulnerabilities to everyday and recurrent stressors and shocks to build resilience to the effects of El Niño and other extremes in climate and weather.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01321-z) contains supplementary material, which is available to authorized users.