The edge of a monsoon region is usually highly sensitive to climate change. Pakistan, which located on the northern Indian monsoon, vulnerable heavy rainfall and has witnessed several debilitating floods exacerbated by global warming in recent years. However, mechanisms for frequent Pakistan are yet not fully understood. Here, we show that Middle East undergoing an increase land heating during spring, responsible 46% intensified over northwestern India 1979-2022. This springtime causes...

A clear understanding of landslide mechanisms and stability analyses is great significance for monitoring, prediction, control. large-scale end wall occurred its area reached 47,752 m 2 on August 7–20, 2020, in the Manglai open-pit coal mine, China. In this paper, engineering geological survey, mechanical test, large-deformation finite element numerical method, limit equilibrium method analytical formula are used to analyze how groundwater level rise caused failure landslide. The conditions,...

Abstract The western North Pacific summer monsoon (WNPSM) is characterized by prominent northward propagation of intraseasonal oscillations (ISOs). However, the specific vorticity dynamics as an atmospheric precursor responsible for ISOs remains unclear over WNPSM. In this study, we utilized a multi‐timescale diagnosis to identify key in Our findings indicate that both vortex tilting and advection play important roles generation subsequent development new convection, ultimately leading ISO...

Abstract The simulation of the northward‐propagating monsoon intraseasonal oscillation (MISO) is still a grand challenge for climate models. Here, we show that tilting vorticity plays critical role in MISO. During Indian summer (ISM), persistent vertical easterly shear background zonal wind sets up horizontal vorticity. Due to meridional gradient velocity associated with convection, positive anomalies are generated north where convection enhanced. In 19 coupled general circulation models...

Abstract Intraseasonal oscillation (ISO) is the dominant variability during Indian summer monsoon (ISM). In this study, it found that ISOs accompanying intraseasonal rainfall are substantially enhanced over northeastern Arabian Sea (AS) in past three decades. The rise agrees with variation moisture loading. strengthening of wind convergence planetary boundary layer (PBL) triggers changes vertical velocity, intensifying advection background by which contributes most to intensified supply AS....

Abstract Tropical cyclones (TCs) can be modified by various processes in the multiscale weather and climate system. In this study, TC genesis locations are found to shift northward Bay of Bengal (BoB) due intraseasonal central Indian Ocean (CIO) mode. During positive phase CIO mode, convection center moves from equator BoB. Correspondingly, over BoB, updraft transports moisture mid‐troposphere, associated convergence cyclonic vorticity lower troposphere favorable for genesis. The diagnoses...

Abstract The predictability limits of tropical cyclone (TC) intensity over the western North Pacific (WNP) are investigated using TC best track data. results show that limit minimum central pressure (MCP) is ~102 h, comparable to maximum sustained wind (MSW). spatial distribution MCP WNP similar MSW, and both gradually decrease from eastern (EWNP) South China Sea (SCS). MSW relatively high southeastern where modified accumulated energy (MACE) large, whereas they low SCS MACE small. patterns...

Abstract The simulations of the monsoon intraseasonal oscillation (MISO) during Indian summer (ISM) are evaluated with 19 atmosphere–ocean coupled general circulation models (CGCMs) from phase 6 Coupled Model Inter-comparison Project (CMIP6). focus is on northward propagation MISO. CMIP6 have great improvement in simulating mean rainfall, as 17 out can reasonably simulate rainfall. However, many fail to reproduce realistic patterns rainfall and MISO amplitude, particularly over land region....

Abstract A high surface air temperature (SAT) record over Northwestern India was reported in April 2022. This study examines the contribution of interannual variability on Indian SAT and possible reasons for extreme during Result shows that is captured by first two leading modes using empirical orthogonal function (EOF) analysis. Both them show highest values are simultaneous energetic The EOF1 related to Ocean Basin Mode (IOBM) an anomalous anti-cyclone troposphere, while Rossby wave train...

Abstract The Monsoon intraseasonal oscillation (MISO) is the predominant variability over tropical Indian Ocean during summer monsoon. A cyclonic vortex plays a critical role in northward propagation of MISO. Here, we find that pronounced kinetic energy accompanying attributable to barotropic gain from background circulation. In particular, due phase shift between and low‐level horizontal wind convergence, covariance easterly downdraft reinforces before vortex. contrast, interaction westerly...

Abstract Simulation of monsoon intraseasonal oscillations (MISO) during the Indian summer (ISM) is a grand scientific challenge. The Subseasonal‐to‐Seasonal (S2S) prediction project provides unique way to examine key dynamics MISO. Recently, Central Ocean (CIO) mode was proposed as an intrinsic climate over Ocean, and it has close relation with MISO ISM. In this study, simulations CIO events in S2S models are examined. results confirm that better rendition tends result simulation northward...

Abstract Fluctuations in climatic proxies of the Milanggouwan section Salawusu River valley Ordos Plateau (Inner Mongolia, China) during Marine Isotope stage 3 (MIS 3) coincide well with sedimentary cycles for palaeo‐mobile dune sands alternating fluvial–lacustrine facies and palaeosols. We compared modern mobile (products a cold dry climate dominated by East Asian winter monsoon), whereas palaeosols were controlled wet–warm similar to that summer monsoon. The MIS appears have experienced at...

For an n-dimensional chaotic system, we extend the definition of nonlinear local Lyapunov exponent (NLLE) from one- to spectra, and present a method for computing NLLE spectrum. The is tested on three systems with different complexity. results indicate that spectrum realistically characterizes growth rates initial error vectors along directions linear phases growth. This represents improvement over traditional spectrum, which only during phase In addition, because can effectively separate...

Abstract In recent decades, an increase in rainfall has been observed on the northwestern edge of Indian summer monsoon (ISM; NWEISM). However, no studies have focused model performances over NWEISM, which calls for urgent evaluation models. Here, we utilize historical simulations from 24 CMIP6 models to demonstrate that current tend underestimate increasing with only ∼30% intensity. The broadly capture spring Middle East land warming, is main driver increased NWEISM. Unfortunately, most...

Abstract This study diagnoses the drivers of intraseasonal variability mixed layer chlorophyll‐a (Chl) concentration in tropical Indian Ocean during boreal summer (June–September) using a well‐tested coupled ocean‐ecosystem model. Results show that wind forcing is primary source for energetic Chl eastern Arabian Sea and western Bay Bengal (BoB) modulated by Central (CIO) mode. The atmospheric anomalous anticyclone associated with positive phase CIO mode drives southeastward currents Sea,...

Interdecadal changes in the potential predictability of East Asian summer monsoon (EASM) and South (SASM) were investigated using signal‐to‐noise ratio daily reanalysis data from 1948 to 2017. Results reveal that variations SASM are out phase with those EASM predictability, is higher (lower) than before (after) 1980s. The out‐of‐phase relationship two systems attributed mainly temporal their relationships El Niño‐Southern Oscillation (ENSO). between ENSO related position heating center,...

The prediction of monsoonal precipitation during Indian summer monsoon (ISM) remains difficult. Due to the high correlation between Central Ocean (CIO) mode index and ISM variability, predictability limit CIO is investigated by non-linear local Lyapunov exponent (NLLE) method in observations. Results show that can reach 38 days boreal (from June September), which close upper intraseasonal (up 40 days), higher than limits dynamical indices (under 3 weeks) oscillation (BSISO) (around 30 days)....

Abstract Diapausing populations of Calanus finmarchicus at depth in the Lofoten Basin (LB) return to continental shelf and slope off Lofoten‐Vesterålen Islands during phytoplankton spring bloom feed spawn, forming surface swarms with a great abundance. To study how overwintering C. move deep currents shelf, Lagrangian transport characteristics particles water between 2008 2019 were analyzed using Global Ocean Reanalysis Simulation re‐analysis data Coherent Structures (LCSs). Our analyses...

Abstract The simulation and prediction of the Indian summer monsoon (ISM) its intraseasonal component in climate models remain a grand scientific challenge for models. Recently, an mode was proposed over tropical Ocean, named central Ocean (CIO) mode. CIO index with oscillations (MISO) have high correlation. In this study, simulations sixth phase Coupled Model Intercomparison Project (CMIP6) are examined. Although coupled ocean-atmosphere feedbacks associated not fully reproduced, results...

Abstract The sudden halting of the extreme 2014/15 El Niño expected by many was attributed to absence westerly wind bursts (WWBs) in late spring and early summer 2014 previous works, yet cause lack WWBs overlooked. Using ERA5 reanalysis IBTrACS dataset, as well a set coupled model experiments, we showed that May efficiently downgraded intensity from moderate weak event closely associated with strong suppressive MJO originating central tropical Indian Ocean mid-April 2014. underwent two...

Abstract The Pacific meridional mode (PMM) is one of the dominant coupled modes in northeastern tropical (NETP), characterized by strip-like sea surface temperature (SST) anomalies spanning from Baja California to central equatorial Pacific. While majority El Niño events follow a positive PMM, only few La Niña are preceded negative PMM. Such an asymmetric activity PMM before onset Niño–Southern Oscillation (ENSO) was previously attributed inherent nonlinear response wind–evaporation–SST...