scholarly journals Coral Cd/Ca and Mn/Ca records of ENSO variability in the Gulf of California

2010 ◽  
Vol 6 (3) ◽  
pp. 401-410 ◽  
Author(s):  
J. D. Carriquiry ◽  
J. A. Villaescusa

Abstract. We analyzed the trace element ratios Cd/Ca and Mn/Ca in three coral colonies (Porites panamensis (1967–1989), Pavona clivosa (1967–1989) and Pavona gigantea (1979–1989)) from Cabo Pulmo reef, Southern Gulf of California, Mexico, to assess the oceanographic changes caused by El Niño – Southern Oscillation (ENSO) events in the Eastern Tropical North Pacific (ETNP). Interannual variations in the coral Cd/Ca and Mn/Ca ratios showed clear evidence that incorporation of Cd and Mn in the coral skeleton was influenced by ENSO conditions, but the response for each metal was controlled by different processes. The Mn/Ca ratios were significantly higher during ENSO years (p<0.05) relative to non-ENSO years for the three species of coral. In contrast, the Cd/Ca was systematically lower during ENSO years, but the difference was significant (p<0.05) only in Pavona gigantea. A decrease in the incorporation of Cd and a marked increase in Mn indicated strongly reduced vertical mixing in the Gulf of California during the mature phase of El Niño. The oceanic warming during El Niño events produces a relaxation of upwelling and a stabilization of the thermocline, which may act as a physical barrier limiting the transport of Cd from deeper waters into the surface layer. In turn, this oceanic condition can increase the residence time of particulate-Mn in surface waters, allowing an increase in the photo-reduction of particulate-Mn and the release of available Mn into the dissolved phase. These results support the use of Mn/Ca and Cd/Ca ratios in biogenic carbonates as tracers of increases in ocean stratification and trade wind weakening and/or collapse in the ETNP during ENSO episodes.

2010 ◽  
Vol 6 (1) ◽  
pp. 63-85 ◽  
Author(s):  
J. D. Carriquiry ◽  
J. A. Villaescusa

Abstract. We analyzed the trace element ratios Cd/Ca and Mn/Ca in three coral colonies (Pavona gigantea, Pavona clivosa and Porites panamensis) from Cabo Pulmo reef, Southern Gulf of California, Mexico, to assess the oceanographic changes caused by El Niño – Southern Oscillation (ENSO) events in the Eastern Tropical North Pacific (ETNP). The interannual variations in the coral Cd/Ca and Mn/Ca ratios show clear evidence that incorporation of Cd and Mn in the coral skeleton are influenced by ENSO conditions, but the response for each metal is controlled by different process. The Mn/Ca ratios were significantly higher during ENSO years (p<0.05) relative to non-ENSO years for the three species of coral. In contrast, the Cd/Ca was systematically lower during ENSO years, but it was significant (p<0.05) only in P. gigantea. The decrease in the incorporation of Cd, and the marked increase in Mn during the mature phase of El Niño indicate strongly reduced vertical mixing in the Gulf of California. The oceanic warming during El Niño events produces a relaxation of upwelling and a stabilization of the thermocline which acts as a physical barrier limiting the transport of Cd from deeper waters into the surface layer. In turn, this oceanic condition can increase the residence time of particulate-Mn in surface waters, which in turn increases the photo-reduction of particulate-Mn and the release of the available Mn into the dissolved phase. These results provide validation for using Mn/Ca and Cd/Ca in biogenic carbonates as tracers of changes in ocean stratification and trade wind weakening and/or collapse in the ETNP during ENSO episodes.


2021 ◽  
pp. 1-47
Author(s):  
XIAODAN YANG ◽  
YAJUAN SONG ◽  
MENG WEI ◽  
YUHUAN XUE ◽  
ZHENYA SONG

AbstractIn this paper, the different effects of the eastern equatorial Pacific (EP) and central equatorial Pacific (CP) El Niño-Southern Oscillation (ENSO) events on interannual variation in the diurnal sea surface temperature (SST) are explored in both the Niño 3 and Niño 4 regions. In the Niño 3 region, the diurnal SST anomaly (DSSTA) is negative during both EP and CP El Niño events and becomes positive during both EP and CP La Niña events. However, the DSSTA in the Niño 4 region is positive in El Niño years and negative in La Niña years, which is opposite to that in the Niño 3 region. Further analysis indicates that the incident shortwave radiation (SWR), wind stress (WS), and upward latent heat flux (LHF) are the main factors causing the interannual variation in the DSST. In the Niño 3 region, the decreased/increased SWR and the increased (decreased) LHF lead to the negative (positive) DSSTA in EP El Niño (La Niña) years. In addition, the enhanced (reduced) WS and the increased (decreased) LHF cause the negative (positive) DSSTA in CP El Niño (La Niña) years. In the Niño 4 region, the reduced (enhanced) trade wind plays a key role in producing in the positive (negative) DSSTA, while the decreased (increased) SWR has an opposite effect that reduces/increases the range of the DSSTA during both EP and CP El Niño (La Niña) events.


2013 ◽  
Vol 26 (13) ◽  
pp. 4710-4724 ◽  
Author(s):  
Michael Mayer ◽  
Kevin E. Trenberth ◽  
Leopold Haimberger ◽  
John T. Fasullo

Abstract The variability of zonally resolved tropical energy budgets in association with El Niño–Southern Oscillation (ENSO) is investigated. The most recent global atmospheric reanalyses from 1979 to 2011 are employed with removal of apparent discontinuities to obtain best possible temporal homogeneity. The growing length of record allows a more robust analysis of characteristic patterns of variability with cross-correlation, composite, and EOF methods. A quadrupole anomaly pattern is found in the vertically integrated energy divergence associated with ENSO, with centers over the Indian Ocean, the Indo-Pacific warm pool, the eastern equatorial Pacific, and the Atlantic. The smooth transition, particularly of the main maxima of latent and dry static energy divergence, from the western to the eastern Pacific is found to require at least two EOFs to be adequately described. The canonical El Niño pattern (EOF-1) and a transition pattern (EOF-2; referred to as El Niño Modoki by some authors) form remarkably coherent ENSO-related anomaly structures of the tropical energy budget not only over the Pacific but throughout the tropics. As latent and dry static energy divergences show strong mutual cancellation, variability of total energy divergence is smaller and more tightly coupled to local sea surface temperature (SST) anomalies and is mainly related to the ocean heat discharge and recharge during ENSO peak phases. The complexity of the structures throughout the tropics and their evolution during ENSO events along with their interactions with the annual cycle have often not been adequately accounted for; in particular, the El Niño Modoki mode is but part of the overall evolutionary patterns.


2015 ◽  
Vol 11 (10) ◽  
pp. 1325-1333 ◽  
Author(s):  
K. Schollaen ◽  
C. Karamperidou ◽  
P. Krusic ◽  
E. Cook ◽  
G. Helle

Abstract. Indonesia's climate is dominated by the equatorial monsoon system, and has been linked to El Niño-Southern Oscillation (ENSO) events that often result in extensive droughts and floods over the Indonesian archipelago. In this study we investigate ENSO-related signals in a tree-ring δ18O record (1900–2007) of Javanese teak. Our results reveal a clear influence of Warm Pool (central Pacific) El Niño events on Javanese tree-ring δ18O, and no clear signal of Cold Tongue (eastern Pacific) El Niño events. These results are consistent with the distinct impacts of the two ENSO flavors on Javanese precipitation, and illustrate the importance of considering ENSO flavors when interpreting palaeoclimate proxy records in the tropics, as well as the potential of palaeoclimate proxy records from appropriately selected tropical regions for reconstructing past variability of. ENSO flavors.


1994 ◽  
Vol 6 (4) ◽  
pp. 473-478 ◽  
Author(s):  
C. Guinet ◽  
P. Jouventin ◽  
J-Y. Georges

The population trend over the last decade for subantarctic fur seals (Arctocephalus tropicalis) on Amsterdam and St. Paul islands and on Possession Island (Crozet Archipelago) and Antarctic fur seals (A. gazella) on Possession Island are analysed. At Amsterdam Island, based on pup counts, the subantarctic fur seal population appears to have stabilized after a period of rapid growth. At Possession Island subantarctic fur seal and Antarctic fur seal, with respective annual growth rates of 19.2 and 17.4%, are reaching the maximum growth rate for the genus Arctocephalus. Annual pup censuses at Possession Island since 1978 indicate important variations from year to year with pup production for A. gazella significantly lower the year after an El Niño Southern Oscillation (ENSO) event, but with no such relationship for A. tropicalis. Several other long term demographic studies of seabirds and marine mammals at different breeding locations in the Southern Ocean indicate that the breeding success of several of these predators appears to be widely affected in years which appear to be related to the ENSO events. To clarify this, it is necessary to analyse in more detail the demographic data obtained for the different subantarctic and Antarctic locations where long term monitoring programmes are conducted.


2008 ◽  
Vol 21 (1) ◽  
pp. 84-93 ◽  
Author(s):  
Jing-Jia Luo ◽  
Sebastien Masson ◽  
Swadhin K. Behera ◽  
Toshio Yamagata

Abstract Using a fully coupled global ocean–atmosphere general circulation model assimilating only sea surface temperature, the authors found for the first time that several El Niño–Southern Oscillation (ENSO) events over the past two decades can be predicted at lead times of up to 2 yr. The El Niño condition in the 1997/98 winter can be predicted to some extent up to about a 1½-yr lead but with a weak intensity and large phase delay in the prediction of the onset of this exceptionally strong event. This is attributed to the influence of active and intensive stochastic westerly wind bursts during late 1996 to mid-1997, which are generally unpredictable at seasonal time scales. The cold signals in the 1984/85 and 1999/2000 winters during the peak phases of the past two long-lasting La Niña events are predicted well up to a 2-yr lead. Amazingly, the mild El Niño–like event of 2002/03 is also predicted well up to a 2-yr lead, suggesting a link between the prolonged El Niño and the tropical Pacific decadal variability. Seasonal climate anomalies over vast parts of the globe during specific ENSO years are also realistically predicted up to a 2-yr lead for the first time.


2019 ◽  
Vol 32 (22) ◽  
pp. 7643-7661 ◽  
Author(s):  
Dillon J. Amaya ◽  
Yu Kosaka ◽  
Wenyu Zhou ◽  
Yu Zhang ◽  
Shang-Ping Xie ◽  
...  

Abstract Studies have indicated that North Pacific sea surface temperature (SST) variability can significantly modulate El Niño–Southern Oscillation (ENSO), but there has been little effort to put extratropical–tropical interactions into the context of historical events. To quantify the role of the North Pacific in pacing the timing and magnitude of observed ENSO, we use a fully coupled climate model to produce an ensemble of North Pacific Ocean–Global Atmosphere (nPOGA) SST pacemaker simulations. In nPOGA, SST anomalies are restored back to observations in the North Pacific (&gt;15°N) but are free to evolve throughout the rest of the globe. We find that the North Pacific SST has significantly influenced observed ENSO variability, accounting for approximately 15% of the total variance in boreal fall and winter. The connection between the North and tropical Pacific arises from two physical pathways: 1) a wind–evaporation–SST (WES) propagating mechanism, and 2) a Gill-like atmospheric response associated with anomalous deep convection in boreal summer and fall, which we refer to as the summer deep convection (SDC) response. The SDC response accounts for 25% of the observed zonal wind variability around the equatorial date line. On an event-by-event basis, nPOGA most closely reproduces the 2014/15 and the 2015/16 El Niños. In particular, we show that the 2015 Pacific meridional mode event increased wind forcing along the equator by 20%, potentially contributing to the extreme nature of the 2015/16 El Niño. Our results illustrate the significant role of extratropical noise in pacing the initiation and magnitude of ENSO events and may improve the predictability of ENSO on seasonal time scales.


2019 ◽  
Vol 32 (2) ◽  
pp. 150-157
Author(s):  
Gillian Phillips ◽  
David M Hudson ◽  
Jenny J Chaparro-Gutiérrez

Background: Paragonimus spp. are trematode parasites that infect human populations worldwide. It is believed that infection rates within Asia reach five to ten percent of the total population. Three of the largest areas of possible infection are Asia, Central and South America as well as Africa, where the total population at risk is estimated to be 293 million people. Humans are infected via ingestion of raw or undercooked decapod crustaceans. Objective: To identify the presence of Paragonimus spp. in crabs from Bogotá, Colombia. Methods: The native crab Neostrengeria macropa and the aquatic invasive crayfish Procambarus clarkii in Bogotá, Colombia, were collected from local markets, pet stores and waterways and dissected to assess the presence of Paragonimus spp.  Results: The native crab species, N. macropa (n=29) had an infection prevalence of 17.2%, while the invasive crayfish species, P. clarkii (n=22), had a prevalence of 36.4% combined from both field captured animals and purchased samples. Conclusion: Although the estimated prevalence is lower compared to previous studies in other cities of Colombia, Paragonimus represent a risk to human health. Several environmental factors may contribute to the difference in prevalence including collecting season, rainfall, temperature, altitude and the El Niño Southern Oscillation. Keywords: crabs, invasive species, Neostrengeria macropa, Procambarus clarkii, trematode. ResumenAntecedentes: Los Paragonimus spp. constituyen un grupo de parásitos tremátodos que infectan a humanos en todo el mundo. Se considera que entre 5 y 10% de la población humana de Asia está infectada. Las áreas con mayor posibilidad de infección son Asia, Centro y Sur América, así como África. Se estima que 293 millones de personas están en riesgo de infección. Los humanos se pueden infectar al consumir crustáceos decápodos crudos. Objetivo: Identificar la presencia de Paragonimus spp. en crustáceos en Bogotá, Colombia. Métodos: Una muestra de cangrejos nativos Neostrengeria macropa y de decápodos invasores Procambarus clarkii fue colectada tanto en mercados locales de Bogotá, como en tiendas de mascotas, ríos, y quebradas. Posteriromente fueron diseccionados para detectar la presencia de Paragonimus spp. Resultados: La prevalencia de la infección en N. macropa (n=29) fue de 17,2%, y en la especie invasora, P. clarkii (n=22), fue de 36,4% (porcentaje combinado de los animales colectados en el campo y los comprados en tiendas). Conclusión: Aunque la prevalencia en este estudio fue más baja que la de otras investigaciones relacionadas, se considera que existe riesgo para la salud humana. Es probable que algunos factores medio ambientales hayan contribuido a la diferencia, incluyendo: temporada de colecta, nivel de lluvias, temperatura, altura, y el fenómeno El Niño. Palabras claves: cangrejos, especie invasora, Neostrengeria macropa, Procambarus clarkii, tremátodo. ResumoAntecedentes: Paragonimus spp. são trematódeos parasitas que infectam populações humanas ao redor do mundo. Acredita-se que as taxas de infecção na Ásia atingem de 5 a 10% da população. As três maiores áreas de infecção se localizam na Ásia, Américas do Sul e Central e África, onde a população total em risco é estimada em 293 milhões de pessoas. Os humanos são infectados pela ingestão de crustáceos decápodes crus ou mal cozidos. Objetivo: Identificar a presença de Paragonimus spp. em Bogotá, Colômbia. Métodos: Indivíduos de caranguejo nativo Neostrengeria macropa e lagostim aquático invasivo Procambarus clarkii  foram coletados em mercados locais, lojas de animais de estimação e cursos de água em Bogotá (Colômbia) e posteriormente dissecados para verificação da presença de Paragonimus spp. Resultados: A espécie de caranguejo nativa N. macropa (n=29) apresentou prevalência de infecção de 17,2%, enquanto a espécie de lagostim invasivo, P. clarkii (n=22), apresentou prevalência de 36,4%, quando combinados os animais capturados em campo e os animais comprados. Conclusão: Embora a prevalência estimada neste estudo foi menor do que a de pesquisas anteriores realizadas em outras cidades da Colômbia, existe um risco para a saúde humana. Há inúmeros fatores ambientais que podem contribuir para a diferença de prevalência, dentre eles: a estação em que a coleta foi realizada, pouca precipitação, temperatura, altitude e a Oscilação Sul-El Niño.Palabras-chave: caranguejos, espécies invasivas, Neostrengeria macropa, Procambarus clarkii, trematódeos.


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