Increased variability of eastern Pacific El Niño under greenhouse warming

Cai, Wenju; Wang, Guojian; Dewitte, Boris; Wu, Lixin; Santoso, Agus; Takahashi, K.; Yang, Yun; Carréric, Aude; McPhaden, Michael J.

doi:10.1038/s41586-018-0776-9

Cited by 480 publications

(441 citation statements)

References 48 publications

Supporting

Mentioning

406

Contrasting

Unclassified

Order By: Relevance

“…The ability to mount a successful defence may become even more challenging in the face of a changing climate [25,62]. Recent models predict increased variability and magnitude of El Niñ o and La Niñ a events [63], which are the primary climatic cycles that drive rainfall patterns in the Galápagos [34]. Our data suggest that even short-term environmental variation can generate radically different costs of parasites to host fitness.…”

Section: Discussionmentioning

confidence: 80%

Annual environmental variation influences host tolerance to parasites

et al. 2019

View full text Add to dashboard Cite

When confronted with a parasite or pathogen, hosts can defend themselves by resisting or tolerating the attack. While resistance can be diminished when resources are limited, it is unclear how robust tolerance is to changes in environmental conditions. Here, we investigate the sensitivity of tolerance in a single host population living in a highly variable environment. We manipulated the abundance of an invasive parasitic fly, Philornis downsi, in nests of Galápagos mockingbirds (Mimus parvulus) over four field seasons and measured host fitness in response to parasitism. Mockingbird tolerance to P. downsi varied significantly among years and decreased when rainfall was limited. Video observations indicate that parental provisioning of nestlings appears key to tolerance: in drought years, mockingbirds likely do not have sufficient resources to compensate for the effects of P. downsi. These results indicate that host tolerance is a labile trait and suggest that environmental variation plays a major role in mediating the consequences of host -parasite interactions.

show abstract

Section: Discussionmentioning

confidence: 80%

Annual environmental variation influences host tolerance to parasites

et al. 2019

View full text Add to dashboard Cite

show abstract

“…ENSO, especially El Niño, has undergone drastic changes in recent decades (Wang & An, 2001;Yang et al, 2018). It is thought to be modulated by mean state changes in terms of both intrinsic climate variability and anthropogenic forcing (An & Bong, 2016;Cai et al, 2018;Choi et al, 2011;Wang et al, 2017;Yeh et al, 2011;Zhong et al, 2017). However, multidecadal intensification of wintertime cross-equatorial winds over the eastern Pacific could weaken ENSO variability by modifying mean vertical thermal stratification and horizontal advections (Hu & Fedorov, 2018).…”

Section: Conclusion and Discussionmentioning

confidence: 99%

Unusual Anomaly Pattern of the 2015/2016 Extreme El Niño Induced by the 2014 Warm Condition

Zhong

Cai

Zheng

et al. 2019

Geophysical Research Letters

Self Cite

View full text Add to dashboard Cite

The warm center of the 2015/2016 extreme El Niño was located further to the west compared to previous extreme events, causing vastly different social-economic impacts. Though many studies investigated ocean-atmosphere couplings responsible for its large magnitude, the dynamics that govern the unique structure of the event remain elusive. Here we show that a local ocean-atmosphere feedback among convection-induced surface winds, oceanic upwelling and sea surface temperature in the far-eastern Pacific, resulted in a boreal summer cooling tendency along the South American coast. It canceled warming in the far-eastern equatorial Pacific that would otherwise develop, leading to the distinctive anomaly pattern of the 2015/2016 El Niño. These processes were initially triggered by the leftover anomalous warm sea surface temperature and positive moist static energy over the northeastern tropical Pacific in the following boreal spring of the 2014 warm event.Plain Language Summary Extreme El Niño events exert severe impacts on society, but predicting extreme events is challenging. These events are rare and distinctive from one to another in their spatial pattern, generating different regional impacts and disasters. In particular, the 2015/2016 extreme El Niño features a more westward warm center of sea surface temperature anomalies, compared to that of 1982/1983 or 1997/1998. Our analysis of observations relates this unique anomaly pattern to the preceding warm tropical Pacific in 2014. That is, rainfall anomalies over the eastern Pacific were initially fueled by the leftover unstable energy over the northeastern tropical Pacific. Then the center of anomalous rainfall was restricted to the north of the equator through a local ocean-atmosphere feedback among convection-induced surface flows, oceanic upwelling and sea surface temperature. The positive feedback resulted in a summer cooling tendency along the South American coast, which offset warm SST anomalies and caused the unusual pattern of the 2015/2016 extreme El Niño. Our further investigation suggested that the state of the eastern Pacific before the developing summer is also essential for the development of other El Niño events.

show abstract

“…Post-dam bank erosion is mainly caused by channel incision (Petts and Gurnell, 2005) and variations in the intra-annual flow regimessuch as the rapid drawdown in water levels in September and October during the recession stage of the TGD (Darby et al, 2002;Deng et al, 2018). Furthermore, climate changein particular the increased variability of the eastern Pacific El Niño under greenhouse warming (Cai et al, 2018)can increase the frequency of extreme rainfall in the Yangtze River basin, as is evident in the catastrophic floods of 2015 and 2016 (Li and Lu, 2017;Mei et al, 2018). In the post-dam period, given the lack of reduction in flood levels, frequent bank erosion and ongoing climate change, there is a continuing risk of flooding in the MYR despite the existence of the TGD.…”

Section: Impact Of Channel Change On Water Level and Flood Controlmentioning

confidence: 99%

Downstream geomorphic impact of the Three Gorges Dam: With special reference to the channel bars in the Middle Yangtze River

Chen

et al. 2019

Earth Surf Processes Landf

View full text Add to dashboard Cite

The Three Gorges Dam (TGD) has altered downstream flow–sediment regimes and led to significant changes in the morphodynamic processes in the Middle Yangtze River (MYR). However, due to the complexity of this large river, the driving forces and implication of the morphodynamic processes remain insufficiently understood. This study selected two typical meandering and bar‐braided reaches, the Zhicheng (ZC) and Shashi (SS) reach, to examine their responses to the TGD operation. The results showed that in the post‐dam period significant channel erosion occurred with a higher erosion rate in the ZC reach (closer to the TGD) compared with the SS reach. The area of the Guanzhou mid‐channel bar (ZC reach) and the Sanba mid‐channel bar (SS reach) shrank by 30 and 90% from 2003 to 2015, respectively. The increased fluvial erosion intensity due to the reduction in suspended sediment concentration (SSC) drove the shrinkage of the mid‐channel bars, as demonstrated by empirical relationships between bar geometry and fluvial erosion intensity. An increase of 22 days per year in the frequency of post‐dam medium‐to‐high discharges (10 000–25 000 m3 s−1), and associated with the reduction in SSC, jointly led to the greater erosion at the convex (inner) banks than the concave (outer) banks, which has negatively affected the designed navigation channels at the concave banks by decreasing their discharge partitioning ratios. The post‐dam water level at a given high discharge (>25 000 m3 s−1) showed no evident change, but the water level at a given low discharge (<10 000 m3 s−1) decreased. The reduction in water levels at low flows can affect water supply and riverine ecosystems in the MYR. © 2019 John Wiley & Sons, Ltd.

show abstract

Increased variability of eastern Pacific El Niño under greenhouse warming

Cited by 480 publications

References 48 publications

Annual environmental variation influences host tolerance to parasites

Annual environmental variation influences host tolerance to parasites

Unusual Anomaly Pattern of the 2015/2016 Extreme El Niño Induced by the 2014 Warm Condition

Downstream geomorphic impact of the Three Gorges Dam: With special reference to the channel bars in the Middle Yangtze River

Contact Info

Product

Resources

About