Bendix, J. and Bendix, A.: Climatological aspects of the 1991/1993 El Nino in Ecuador, Bulletin de l’Institut Français d’Études Andines, 27, 655–666, 1998. a
Bony, S., Lau, K.-M., and Sud, Y. C.: Sea Surface Temperature and Large-Scale Circulation Influences on Tropical Greenhouse Effect and Cloud Radiative Forcing, J. Climate, 10, 2055–2077,
https://doi.org/10.1175/1520-0442(1997)010<2055:sstals>2.0.co;2, 1997.
a,
b,
c,
d,
e,
f,
g
Cornejo-Garrido, A. G. and Stone, P. H.: On the heat balance of the Walker circulation, J. Atmos. Sci., 34, 1155–1162,
https://doi.org/10.1175/1520-0469(1977)034<1155:OTHBOT>2.0.CO;2, 1977.
a,
b,
c,
d,
e
DeMott, C. A. and Randall, D. A.: Observed variations of tropical convective available potential energy, J. Geophys. Res.-Atmos., 109,
https://doi.org/10.1029/2003jd003784, 2004.
a,
b,
c,
d,
e
Douglas, M. W., Mejia, J., Ordinola, N., and Boustead, J.: Synoptic variability of rainfall and cloudiness along the coasts of northern Peru and Ecuador during the 1997/98 El Niño event, Mon. Weather Rev., 137, 116–136, 2009. a
Echevin, V., Colas, F., Espinoza-Morriberon, D., Vasquez, L., Anculle, T., and Gutierrez, D.: Forcings and Evolution of the 2017 Coastal El Niño Off Northern Peru and Ecuador, Front. Mar. Sci., 5,
https://doi.org/10.3389/fmars.2018.00367, 2018.
a,
b
Emanuel, K. A.: Atmospheric convection, Oxford University Press, ISBN 9780195066302, 1994.
a,
b
Emanuel, K. A., David Neelin, J., and Bretherton, C. S.: On large-scale circulations in convecting atmospheres, Q. J. Roy. Meteorol. Soc., 120, 1111–1143, 1994.
a,
b,
c,
d
Emmenegger, T., Ahmed, F., Kuo, Y.-H., Xie, S., Zhang, C., Tao, C., and Neelin, J. D.: The physics behind precipitation onset bias in CMIP6 models: The pseudo-entrainment diagnostic and trade-offs between lapse rate and humidity, J. Climate, 37, 2013–2033,
https://doi.org/10.1175/JCLI-D-23-0382.1, 2024.
a,
b
ERFEN: Boletín Técnico ERFEN Nro. 09-2024, Tech. rep., Comité Nacional para el Estudio Regional del Fenómeno El Niño, Instituto Oceanográfico y Antártico de la Armada del Ecuador (INOCAR),
https://www.inocar.mil.ec/boletin/ERFEN/erfen_20240605.pdf (last access: 2 July 2026), 2024. a
Fernandez-Palomino, C. A., Hattermann, F. F., Krysanova, V., Lobanova, A., Vega-Jácome, F., Lavado, W., Santini, W., Aybar, C., and Bronstert, A.: A novel high-resolution gridded precipitation dataset for Peruvian and Ecuadorian watersheds: Development and hydrological evaluation, J. Hydrometeorol., 23, 309–336,
https://doi.org/10.1175/JHM-D-20-0285.1, 2022.
a,
b,
c,
d,
e,
f,
g
Fu, R., Zhu, B., and Dickinson, R. E.: How do atmosphere and land surface influence seasonal changes of convection in the tropical Amazon?, J. Climate, 12, 1306–1321, 1999.
a,
b,
c,
d
Gálvez, J. M. and Davison, M.: The Gálvez-Davison Index for Tropical Convection, Tech. rep., NOAA/NWS/NCEP Weather Prediction Center,
https://www.wpc.ncep.noaa.gov/international/gdi/GDI_Manuscript_V20161021.pdf (last access: 15 January 2026), 2016.
a,
b,
c
Han, Y., Zhang, M.-Z., Xu, Z., and Guo, W.: Assessing the performance of 33 CMIP6 models in simulating the large-scale environmental fields of tropical cyclones, Clim. Dynam., 58, 1683–1698,
https://doi.org/10.1007/s00382-021-05986-4, 2022.
a
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz‐Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.: The ERA5 global reanalysis, Q. J. Roy. Meteorol. Soc., 146, 1999–2049,
https://doi.org/10.1002/qj.3803, 2020.
a,
b,
c
Horel, J. D. and Cornejo-Garrido, A. G.: Convection along the coast of northern Peru during 1983: Spatial and temporal variation of clouds and rainfall, Mon. Weather Rev., 114, 2091–2105, 1986. a
Huaman, L. and Takahashi, K.: The vertical structure of the eastern Pacific ITCZs and associated circulation using the TRMM Precipitation Radar and in situ data, Geophys. Res. Lett., 43, 8230–8239, 2016. a
Huang, A. T., Kuo, Y.-N., and Lehner, F.: Notable influence of internal variability on the perceived difference between Central and eastern Pacific El Niño teleconnections, Geophys. Res. Lett., 53, e2025GL118422,
https://doi.org/10.1029/2025GL118422, 2026.
a
Insel, N., Poulsen, C. J., and Ehlers, T. A.: Influence of the Andes Mountains on South American moisture transport, convection, and precipitation, Clim. Dynam., 35, 1477–1492, 2009.
a,
b,
c,
d
Jauregui, Y. R. and Takahashi, K.: Simple physical-empirical model of the precipitation distribution based on a tropical sea surface temperature threshold and the effects of climate change, Clim. Dynam., 50, 2217–2237, 2018.
a,
b,
c,
d
Johnson, S. J., Stockdale, T. N., Ferranti, L., Balmaseda, M. A., Molteni, F., Magnusson, L., Tietsche, S., Decremer, D., Weisheimer, A., Balsamo, G., Keeley, S. P. E., Mogensen, K., Zuo, H., and Monge-Sanz, B. M.: SEAS5: the new ECMWF seasonal forecast system, Geosci. Model Dev., 12, 1087–1117,
https://doi.org/10.5194/gmd-12-1087-2019, 2019.
a
Lau, K.-M., Wu, H.-T., and Bony, S.: The Role of Large-Scale Atmospheric Circulation in the Relationship between Tropical Convection and Sea Surface Temperature, J. Climate, 10, 381–392,
https://doi.org/10.1175/1520-0442(1997)010<0381:trolsa>2.0.co;2, 1997.
a,
b,
c,
d,
e,
f,
g,
h
Lindzen, R. S. and Nigam, S.: On the role of sea surface temperature gradients in forcing low-level winds and convergence in the tropics, J. Atmos. Sci., 44, 2418–2436, 1987. a
Lorenz, E. N.: Available potential energy and the maintenance of the general circulation, Tellus, 7, 157–167, 1955. a
MAG: Boletín de Precipitación y Temperatura - Nacional (Abril 2023), Tech. rep., Ministerio de Agricultura y Ganadería, Sistema de Información Pública Agropecuaria (SIPA),
https://sipa.agricultura.gob.ec/boletines/nacionales/precipitacion/2023/boletin_agroclima_abril_2023.pdf (last access: 2 July 2026), 2023. a
Michaelides, S. C.: Limited area energetics of Genoa cyclogenesis, Mon. Weather Rev., 115, 13–26, 1987. a
Neelin, J. D. and Held, I. M.: Modeling tropical convergence based on the moist static energy budget, Mon. Weather Rev., 115, 3–12, 1987.
a,
b
Paek, H., Yu, J., and Qian, C.: Why were the 2015/2016 and 1997/1998 extreme El Niños different?, Geophys. Res. Lett., 44, 1848–1856,
https://doi.org/10.1002/2016gl071515, 2017.
a,
b,
c,
d,
e
Peng, Q., Xie, S.-P., Wang, D., Zheng, X.-T., and Zhang, H.: Coupled ocean-atmosphere dynamics of the 2017 extreme coastal El Niño, Nat. Commun., 10, 298,
https://doi.org/10.1038/s41467-018-08258-8, 2019.
a,
b,
c
Peng, Q., Xie, S.-P., Passalacqua, G. A., Miyamoto, A., and Deser, C.: The 2023 extreme coastal El Niño: Atmospheric and air-sea coupling mechanisms, Sci. Adv., 10,
https://doi.org/10.1126/sciadv.adk8646, 2024.
a,
b,
c,
d
Poulin, A., Huard, D., Favre, A.-C., and Pugin, S.: Importance of tail dependence in bivariate frequency analysis, J. Hydrol. Eng., 12, 394–403,
https://doi.org/10.1061/(ASCE)1084-0699(2007)12:4(394), 2007.
a,
b
Poveda, G., Waylen, P. R., and Pulwarty, R. S.: Annual and inter-annual variability of the present climate in northern South America and southern Mesoamerica, Palaeogeogr. Palaeoclimatol. Palaeoecol., 234, 3–27,
https://doi.org/10.1016/j.palaeo.2005.10.031, 2006.
a,
b,
c
Poveda, G., Mejia, J. F., Arias, P. A., Zuluaga, M. D., Salazar, J. F., Carmona, A. M., Builes-Jaramillo, A., Salas, H. D., Yepes, J., Martinez, J. A., and Bedoya-Soto, J. M.: Climate of Northwestern South America, Oxford University Press,
https://doi.org/10.1093/acrefore/9780190228620.013.966, 2025.
a
Quispe, K.: El Niño Costero 2017: Precipitaciones Extraordinarias en el Norte de Perú, Master's thesis, University of Barcelona, Barcelona, Spain,
https://hdl.handle.net/20.500.14366/1900 (last access: 15 January 2026), 2018. a
Rivas Quispe, P. R., Anderson-Frey, A., and Mcmurdie, L. A.: An index for precipitation on the north coast of Peru using logistic regression, Atmósfera, 38, 55–73,
https://doi.org/10.20937/ATM.53232, 2024.
a,
b,
c
Rollenbeck, R., Orellana-Alvear, J., Bendix, J., Rodriguez, R., Pucha-Cofrep, F., Guallpa, M., Fries, A., and Celleri, R.: The Coastal El Niño event of 2017 in Ecuador and Peru: A weather radar analysis, Remote Sens., 14, 824,
https://doi.org/10.3390/rs14040824, 2022.
a,
b,
c,
d,
e
Rudloff, D., Lübbecke, J. F., and Wahl, S.: Seasonality of feedback mechanisms involved in Pacific coastal Niño events, Clim. Dynam., 63, 58,
https://doi.org/10.1007/s00382-024-07131-y, 2025.
a
Runge, J.: Discovering contemporaneous and lagged causal relations in autocorrelated nonlinear time series datasets, in: Proceedings of the 36th
Conference on Uncertainty in Artificial Intelligence (UAI), pp. 1388–1397, PMLR,
http://proceedings.mlr.press/v124/runge20a.html (last access: 15 January 2026), 2020.
a,
b,
c
Sanabria, J., Carrillo, C. M., and Labat, D.: Unprecedented Rainfall and Moisture Patterns during El Niño 2016 in the Eastern Pacific and Tropical Andes: Northern Perú and Ecuador, Atmosphere, 10, 768,
https://doi.org/10.3390/atmos10120768, 2019.
a,
b,
c
SENAMHI: Boletín Climático Nacional – Abril 2023, Tech. rep., Servicio Nacional de Meteorología e Hidrología del Perú, Lima, Perú,
https://www.gob.pe/institucion/senamhi/informes-publicaciones/4206857-boletin-climatico-nacional-abril-2023 (last access: 2 July 2026), 2023. a
SENAMHI: Boletín Climático Nacional - Abril 2024, Tech. rep., Servicio Nacional de Meteorología e Hidrología del Perú, Lima, Perú,
https://www.gob.pe/institucion/senamhi/informes-publicaciones/5573173-boletin-climatico-nacional-abril-2024 (last access: 2 July 2026), 2024. a
Sobel, A. H., Nilsson, J., and Polvani, L. M.: The weak temperature gradient approximation and balanced tropical moisture waves, J. Atmos. Sci., 58, 3650–3665, 2001.
a,
b,
c,
d
Sulca, J.: Evidence of nonlinear Walker circulation feedbacks on extreme El Niño Pacific diversity: Observations and CMIP5 models, Int. J. Climatol., 41, 2934–2961,
https://doi.org/10.1002/joc.6998, 2021.
a
Sulca, J., Takahashi, K., Espinoza, J., Vuille, M., and Lavado‐Casimiro, W.: Impacts of different ENSO flavors and tropical Pacific convection variability (ITCZ, SPCZ) on austral summer rainfall in South America, with a focus on Peru, Int. J. Climatol., 38, 420–435,
https://doi.org/10.1002/joc.5185, 2017.
a,
b
Sun, Q., Miao, C., Duan, Q., Ashouri, H., Sorooshian, S., and Hsu, K.-L.: A review of global precipitation data sets: Data sources, estimation, and intercomparisons, Rev. Geophys., 56, 79–107, 2018. a
Takahashi, K.: The atmospheric circulation associated with extreme rainfall events in Piura, Peru, during the 1997–1998 and 2002 El Niño events, Ann. Geophys., 22, 3917–3926,
https://doi.org/10.5194/angeo-22-3917-2004, 2004.
a,
b,
c,
d,
e,
f,
g,
h,
i,
j,
k,
l,
m,
n,
o
Takahashi, K., Aliaga-Nestares, V., Avalos, G., Bouchon, M., Castro, A., Cruzado, L., Dewitte, B., Gutiérrez, D., Lavado-Casimiro, W., Marengo, J., Martínez, A., Mosquera-Vásquez, K., and Quispe, N.: The 2017 coastal El Niño, B. Am. Meteorol. Soc., 99, S210–S211,
https://doi.org/10.1175/2018BAMSStateoftheClimate.1, 2018.
a,
b
Trachte, K.: Atmospheric Moisture Pathways to the Highlands of the Tropical Andes: Analyzing the Effects of Spectral Nudging on Different Driving Fields for Regional Climate Modeling, Atmosphere, 9, 456,
https://doi.org/10.3390/atmos9110456, 2018.
a,
b,
c
Williams, E. and Renno, N.: An Analysis of the Conditional Instability of the Tropical Atmosphere, Mon. Weather Rev., 121, 21–36,
https://doi.org/10.1175/1520-0493(1993)121<0021:aaotci>2.0.co;2, 1993.
a,
b,
c,
d,
e
Woodman, R.: Modelo estadístico de pronóstico de las precipitaciones en la costa norte del Perú, El Fenómeno El Niño. Investigación para una prognosis, 1er encuentro de Universidades del Pacífico sur: Memoria, pp. 93–108, 1999.
a,
b,
c,
d
WPC: The Galvez-Davison Index (GDI), NOAA NCEP Weather Prediction Center,
https://www.wpc.ncep.noaa.gov/international/gdi/ (last access: 2 July 2026), 2022. a
Yu, H. and Zhang, M.: Explaining the year-to-year variability of the Eastern Pacific intertropical convergence zone in the boreal spring, J. Geophys. Res.-Atmos., 123, 3847–3856,
https://doi.org/10.1002/2017JD028168, 2018.
a
