scholarly journals USING REMOTE SENSING IN STUDY OF EL NIÑO EXTREME DIFFERENCES BETWEEN 1997/1998 AND 2015/2016

2021 ◽  
Vol 4 (17) ◽  
pp. 83-94
Author(s):  
Ricky Anak Kemarau ◽  
Oliver Valentine Eboy
Keyword(s):  
Remote Sensing ◽  
El Niño ◽  
Land Surface ◽  
Spatial Information ◽  
El Nino ◽  
Hot Spot ◽  
Remote Sensing Data ◽  
El Niño Events ◽  
The Impact ◽  
El Nino Events

The years 1997/1998 and 2015/2016 saw the occurrence of El Niño occur among the worst in human history. Until now there is still a lack of research in studying the degree of El Niño's strength impact on climate and weather, especially in the tropic region. The objective of this study is to study the effectiveness of remote sensing technology in identifying the differences between the 1997/1998 and 2015/2016 El Niño events. This study uses six satellite data and temperature data from the Malaysia Meteorology Department (MMD). The first step of remote sensing data will be through pre-processing, converting digital Numbers (DN) to Land Surface Temperature (LST). The results of the study found that there was a change in the pattern of LST columns during the 1997/1998 and 2015/2016 El Niño events. Spatial patterns change based on Oceanic Niño Index (ONI) values. The results of this study are important because of the importance of spatial information to those responsible for preparing measures to overcome and reduce the impact of El Niño on the population. at the developing country level, including Malaysia, there is still a lack of information technology infrastructure in channeling useful information to the community. Through the information, this spatial information provides critical hot spot information that needs more attention.

scholarly journals Examining the sensitivity of the terrestrial carbon cycle to the expression of El Niño

2020 ◽  
Author(s):  
Lina Teckentrup ◽  
Martin G. De Kauwe ◽  
Andrew J. Pitman ◽  
Benjamin Smith
Keyword(s):  
Carbon Cycle ◽  
El Niño ◽  
El Nino ◽  
Terrestrial Carbon ◽  
Near Surface ◽  
Terrestrial Carbon Cycle ◽  
El Niño Events ◽  
Ep El Niño ◽  
The Impact ◽  
El Nino Events

Abstract. The El Niño‐Southern Oscillation (ENSO) influences the global climate and the variability in the terrestrial carbon cycle on interannual timescales. Two different expressions of El Niño have recently been identified: (i) Central–Pacific (CP) and (ii) Eastern–Pacific (EP). Both types of El Nino are characterised by above average sea surface temperature anomalies in the respective locations. Studies exploring the impact of these expressions of El Niño on the carbon cycle have identified changes in the amplitude of the concentration of interannual atmospheric carbon dioxide (CO2) variability, as well as different lags in terrestrial CO2 release to the atmosphere following increased tropical near surface air temperature. We employ the dynamic global vegetation model LPJ–GUESS within a synthetic experimental framework to examine the sensitivity and potential long term impacts of these two expressions of El Niño on the terrestrial carbon cycle. We manipulated the occurrence of CP and EP events in two climate reanalysis datasets during the later half of the 20th and early 21st century by replacing all EP with CP and separately all CP with EP El Niño events. We found that the different expressions of El Niño affect interannual variability in the terrestrial carbon cycle. However, the effect on longer timescales was negligible for both climate reanalysis datasets. We conclude that capturing any future trends in the relative frequency of CP and EP El Niño events may not be critical for robust simulations of the terrestrial carbon cycle.

scholarly journals The impact of westerly wind bursts on the diversity and predictability of El Niño events: An ocean energetics perspective

2014 ◽  
Vol 41 (13) ◽  
pp. 4654-4663 ◽  
Author(s):  
Shineng Hu ◽  
Alexey V. Fedorov ◽  
Matthieu Lengaigne ◽  
Eric Guilyardi
Keyword(s):  
El Niño ◽  
El Nino ◽  
Westerly Wind ◽  
El Niño Events ◽  
Ocean Energetics ◽  
The Impact ◽  
Wind Bursts ◽  
Westerly Wind Bursts ◽  
El Nino Events

El Niño Modoki Impacts on Australian Rainfall

2009 ◽  
Vol 22 (11) ◽  
pp. 3167-3174 ◽  
Author(s):  
Andréa S. Taschetto ◽  
Matthew H. England
Keyword(s):  
El Niño ◽  
El Nino ◽  
Central Pacific ◽  
Maximum Rainfall ◽  
El Niño Modoki ◽  
El Niño Events ◽  
The Impact ◽  
Sst Anomalies ◽  
Australian Rainfall ◽  
El Nino Events

Abstract This study investigates interseasonal and interevent variations in the impact of El Niño on Australian rainfall using available observations from the postsatellite era. Of particular interest is the difference in impact between classical El Niño events wherein peak sea surface temperature (SST) anomalies appear in the eastern Pacific and the recently termed El Niño “Modoki” events that are characterized by distinct warm SST anomalies in the central Pacific and weaker cold anomalies in the west and east of the basin. A clear interseasonal and interevent difference is apparent, with the maximum rainfall response for Modoki events occurring in austral autumn compared to austral spring for classical El Niños. Most interestingly, the Modoki and non-Modoki El Niño events exhibit a marked difference in rainfall impact over Australia: while classical El Niños are associated with a significant reduction in rainfall over northeastern and southeastern Australia, Modoki events appear to drive a large-scale decrease in rainfall over northwestern and northern Australia. In addition, rainfall variations during March–April–May are more sensitive to the Modoki SST anomaly pattern than the conventional El Niño anomalies to the east.

scholarly journals Examining the sensitivity of the terrestrial carbon cycle to the expression of El Niño

2021 ◽  
Vol 18 (6) ◽  
pp. 2181-2203
Author(s):  
Lina Teckentrup ◽  
Martin G. De Kauwe ◽  
Andrew J. Pitman ◽  
Benjamin Smith
Keyword(s):  
Carbon Cycle ◽  
El Niño ◽  
El Nino ◽  
Terrestrial Carbon ◽  
Near Surface ◽  
Terrestrial Carbon Cycle ◽  
El Niño Events ◽  
Ep El Niño ◽  
The Impact ◽  
El Nino Events

Abstract. The El Niño‐-Southern Oscillation (ENSO) influences the global climate and the variability in the terrestrial carbon cycle on interannual timescales. Two different expressions of El Niño have recently been identified: (i) central Pacific (CP) and (ii) eastern Pacific (EP). Both types of El Niño are characterised by above-average sea surface temperature anomalies at the respective locations. Studies exploring the impact of these expressions of El Niño on the carbon cycle have identified changes in the amplitude of the concentration of interannual atmospheric carbon dioxide (CO2) variability following increased tropical near-surface air temperature and decreased precipitation. We employ the dynamic global vegetation model LPJ-GUESS (Lund–Potsdam–Jena General Ecosystem Simulator) within a synthetic experimental framework to examine the sensitivity and potential long-term impacts of these two expressions of El Niño on the terrestrial carbon cycle. We manipulated the occurrence of CP and EP events in two climate reanalysis datasets during the latter half of the 20th and early 21st century by replacing all EP with CP and separately all CP with EP El Niño events. We found that the different expressions of El Niño affect interannual variability in the terrestrial carbon cycle. However, the effect on longer timescales was small for both climate reanalysis datasets. We conclude that capturing any future trends in the relative frequency of CP and EP El Niño events may not be critical for robust simulations of the terrestrial carbon cycle.

scholarly journals Application of Remote Sensing on El Niño Extreme Effect in Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI)

2021 ◽  
Vol 6 (1) ◽  
pp. 46-56
Author(s):  
Ricky Anak Kemarau ◽  
Oliver Valentine Eboy
Keyword(s):  
Remote Sensing ◽  
El Niño ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Spatial Information ◽  
El Nino ◽  
Extreme Temperature ◽  
Water Index ◽  
Normalized Difference Water Index ◽  
The Impact

The years 1997/1998 and 2015/2016 saw the worst El Niño occurrence in human history. The occurrence of El Niño causes extreme temperature events which are higher than usual, drought and prolonged drought. The incident caused a decline in the ability of plants in carrying out the process of photosynthesis. This causes the carbon dioxide content to be higher than normal. Studies on the effects of El Niño and its degree of strength are still under-studied especially by researchers in the tropics. This study uses remote sensing technology that can provide spatial information. The first step of remote sensing data needs to go through the pre-process before building the NDVI (Normalized Difference Vegetation Index) and Normalized Difference Water Index (NDWI) maps. Next this study will identify the relationship between Oceanic Nino Index (ONI) with Application Remote Sensing in The Study Of El Niño Extreme Effect 1997/1998 and 2015/2016 On Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI)NDWI and NDWI landscape indices. Next will make a comparison, statistical and spatial information space between NDWI and NDVI for each year 1997/1998 and 2015/2016. This study is very important in providing spatial information to those responsible in preparing measures in reducing the impact of El Niño.

scholarly journals Effects of the 2016 El Niño on the Galapagos artisanal coastal fin-fish fishery

2018 ◽  
Author(s):  
Jose R Marin Jarrin ◽  
Pelayo Salinas-de-León
Keyword(s):  
Climate Change ◽  
Fish Species ◽  
El Niño ◽  
El Nino ◽  
Predatory Fish ◽  
Trophic Chain ◽  
El Niño Events ◽  
Catch Composition ◽  
The Impact ◽  
El Nino Events

El Niño events heavily influence physical characteristics in the Tropical Eastern Pacific and lead to a decrease in nutrient and phytoplankton concentrations and to variation in the composition of the marine trophic chain. However, El Niño events can also provide an opportunity to evaluate the possible effects climate change may have on marine ecosystems. The Galapagos Marine Reserve coastal fin-fish fishery supports approximately 400 fishers that target species that include benthic/demersal predatory fish such as the endemic Galapagos whitespotted sandbass (Paralabrax albomaculatus), the regional endemic sailfin grouper (Mycteroperca olfax) and mottled scorpion fish (Pontinus clemensi), and the misty grouper (Hyporthodon mystacinus). The first two species are listed as vulnerable and endangered, respectively, on the IUCN red list of threatened species. Despite their potential effects on the biota, at present it is unclear how El Niño events influence artisanal fin-fish fisheries in the Galapagos. To study the impacts of El Niño events on the fishery, numerical percentage catch composition at the largest dock in Santa Cruz Island was recorded during March and April 2013, 2014 and 2016 and compared. Compositions were significantly different between 2016 and both 2013 and 2014, but not between 2013 and 2014. These differences appear to have been due to the appearance of uncommon demersal/benthic predatory fish such as Grape eye seabass (Hemilutjanus macrophthalmos) and Pacific dog snapper (Lutjanus novemfasciatus). Size frequency distributions also varied, with significantly larger sizes of several species observed in 2016 when compared to 2013 or 2014. These changes in catch composition and size may be a product of a reduction in nutrient concentration and primary production that led to an increase in water clarity and decrease in prey biomass that forced these benthic fish species to change their feeding behavior and strike at baits that usually would not be easily detected. Because of the conservative life history many of these benthic predatory fish exhibit and the absence of any form of management for fish species in the GMR, El Niño events may have profound effects on their populations due to the elimination of the largest individuals. Management actions, such as size and catch limits and closures, directed at reducing the impact of the fishery on these important fish populations in the near- (El Niños) and long-term (climate change) future should be encouraged.

scholarly journals A Major Ecosystem Shift in Coastal East African Waters During the 1997/98 Super El Niño as Detected Using Remote Sensing Data

2020 ◽  
Vol 12 (19) ◽  
pp. 3127
Author(s):  
Zoe L. Jacobs ◽  
Fatma Jebri ◽  
Meric Srokosz ◽  
Dionysios E. Raitsos ◽  
Stuart C. Painter ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Indian Ocean ◽  
El Niño ◽  
El Nino ◽  
Remote Sensing Data ◽  
Temporary Increase ◽  
Wind Stress Curl ◽  
Indian Ocean Dipole Event ◽  
The Impact ◽  
Super El Niño

Under the impact of natural and anthropogenic climate variability, upwelling systems are known to change their properties leading to associated regime shifts in marine ecosystems. These often impact commercial fisheries and societies dependent on them. In a region where in situ hydrographic and biological marine data are scarce, this study uses a combination of remote sensing and ocean modelling to show how a stable seasonal upwelling off the Kenyan coast shifted into the territorial waters of neighboring Tanzania under the influence of the unique 1997/98 El Niño and positive Indian Ocean Dipole event. The formation of an anticyclonic gyre adjacent to the Kenyan/Tanzanian coast led to a reorganization of the surface currents and caused the southward migration of the Somali–Zanzibar confluence zone and is attributed to anomalous wind stress curl over the central Indian Ocean. This caused the lowest observed chlorophyll-a over the North Kenya banks (Kenya), while it reached its historical maximum off Dar Es Salaam (Tanzanian waters). We demonstrate that this situation is specific to the 1997/98 El Niño when compared with other the super El-Niño events of 1972,73, 1982–83 and 2015–16. Despite the lack of available fishery data in the region, the local ecosystem changes that the shift of this upwelling may have caused are discussed based on the literature. The likely negative impacts on local fish stocks in Kenya, affecting fishers’ livelihoods and food security, and the temporary increase in pelagic fishery species’ productivity in Tanzania are highlighted. Finally, we discuss how satellite observations may assist fisheries management bodies to anticipate low productivity periods, and mitigate their potentially negative economic impacts.

scholarly journals Analisis Fenomena El Nino dan Dampaknya Terhadap Neraca Air Lahan di Pulau Ambon

2019 ◽  
Vol 15 (2) ◽  
pp. 111-118
Author(s):  
Samuel Laimeheriwa ◽  
Mitha Pangaribuan ◽  
Martha Amba
Keyword(s):  
Water Balance ◽  
El Niño ◽  
Agricultural Land ◽  
El Nino ◽  
Extreme Rainfall ◽  
Climatic Data ◽  
El Niño Events ◽  
The Impact ◽  
Land Water ◽  
El Nino Events

El Nino is one of the global phenomena that has affected the climate system of Indonesia, including Ambon Island of Maluku. One of the direct impacts of the El Nino phenomenon is the decrease of water availability on agricultural land. This study aimed: i) to analyze the period of El-Nino extreme rainfall events in  Ambon Island as well as the intensity and its frequency; and ii) to analyze the impact of El Nino events on the water balance of agricultural lands on Ambon Island. Sixty years of climatic data period 1959-2018 from Pattimura Meteorological Station and Karang Panjang Geophysics Station were used to analyze extreme rainfall conditions of El Nino, and to calculate the water balance of land using the methods of  Thornthwaite and Mather (1957). The results showed that 16 times El Nino events occurred in Ambon between 1959 and 2018, with the frequency of 1-7 times per year or four times per year.  The most extreme El Nino events that occurred in Ambon were in 1977, 1987 and 1997.  The results of land water balance calculation during the El-Nino events showed seven months water deficit (September to March) which is 62,6% higher than the normal conditions;  meanwhile, the optimum soil moisture occurred four months (June to September) or seven months shorter than the normal conditions which were 11 months (March to January). Keywords: Ambon Island, El Nino, land-water balance   ABSTRAK El Nino merupakan salah satu fenomena global yang berdampak terhadap sistem iklim di wilayah Indonesia; termasuk wilayah Pulau Ambon Provinsi Maluku. Salah satu dampak langsung fenomena El Nino terhadap sistem pertanian adalah berkurangnya ketersediaan air pada lahan pertanian. Penelitian bertujuan untuk: a) menganalisis tahun-tahun kejadian curah hujan ekstrim El Nino serta intensitas dan frekuensinya di Pulau Ambon; dan b) menganalisis dampak kejadian El Nino terhadap neraca air lahan pertanian di Pulau Ambon. Penelitian ini menggunakan data iklim selama 60 tahun pengamatan periode 1959-2018 dari Stasiun Meteorologi Pattimura Ambon dan Stasiun Geofisika Karang Panjang Ambon. Analisis data iklim dilakukan dengan tahapan sebagai berikut: a) analisis curah hujan pada kondisi ekstrim El Nino; dan b) perhitungan neraca air lahan menggunakan metode Thornthwaite dan Mather (1957). Hasil penelitian menunjukkan bahwa selama periode 1959-2018 kejadian El Nino berlangsung di Pulau Ambon sebanyak 16 kali dengan frekuensi 1-7 tahun sekali atau rata-rata 4 tahun sekali. Tahun-tahun kejadian El Nino di wilayah Pulau Ambon yang paling ekstrim terjadi pada tahun 1977, 1987 dan 1997. Berdasarkan perhitungan neraca air lahan, ketika El-Nino berlangsung defisit air terjadi selama 7 bulan (September sampai dengan Maret); nilainya bertambah sebesar 626% dari kondisi normal, dan kadar air tanah pada kondisi optimum hanya 4 bulan (Juni sampai dengan September) atau lebih pendek 7 bulan dibandingkan kondisi normalnya, yaitu 11 bulan (Maret sampai dengan Januari). Kata kunci: El Nino, neraca air lahan, Pulau Ambon

The Role ofProsopisin Ecological and Landscape Change in the Samaca Basin, Lower Ica Valley, South Coast Peru from the Early Horizon to the Late Intermediate Period

2009 ◽  
Vol 20 (2) ◽  
pp. 303-332 ◽  
Author(s):  
David G. Beresford-Jones ◽  
Susana Arce T. ◽  
Oliver Q. Whaley ◽  
Alex J. Chepstow-Lusty
Keyword(s):  
El Niño ◽  
Landscape Change ◽  
El Nino ◽  
Dry Forest ◽  
South Coast ◽  
Intermediate Period ◽  
Early Intermediate Period ◽  
El Niño Events ◽  
The Impact ◽  
El Nino Events

AbstractThe lower Ica Valley on the hyperarid south coast of Peru is today largely depopulated and bereft of cultivation, yet its extensive archaeological remains attest to substantial prehispanic populations. This paper describes archaeological investigations to retrace changes in geomorphology, ecology, and land-use in Samaca, one of the riparian oasis basins of the lower Río lea, with the aim of investigating when, how, and why such changes took place. Archaeological interpretations of culture change in the region often invoke the impacts of major ENSO perturbations (El Niño). While our investigations confirm that major El Niño events around the end of the Early Intermediate Period likely offer part of the explanation for marked landscape change in the Samaca Basin, we also demonstrate the significance of more gradual, human-induced destruction of Prosopis pallida (huarango) riparian dry-forest. Huarango is a remarkable leguminous hardwood that lives for over a millennium and provides forage, fuel, and food. Moreover, it plays a crucial role in integrating fragile desert ecosystems, enhancing soil fertility and moisture, and accomplishing desalination and microclimatic amelioration. We propose that south coast valleys remained densely forested well into the Early Intermediate Period, attenuating the impact of El Niño events and supporting hitherto underappreciated agroforestry adaptations. Gradual deforestation eventually crossed an environmental threshold: river and wind erosion increased dramatically and precipitated radical desertification, feeding back into cultural changes in the Middle Horizon. Thus we argue Prosopis-human ecological relationships merit proper recognition in our archaeological interpretations of the south coast of Peru.

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