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|Chan, S. C., & Misra, V. (2011). Dynamic Downscaling of the North American Monsoon with the NCEP-Scripps Regional Spectral Model from the NCEP CFS Global Model. J. Climate, 24(3), 653–673.|
|Chan, S. C., & Misra, V. (2010). A Diagnosis of the 1979-2005 Extreme Rainfall Events in the Southeastern United States with Isentropic Moisture Tracing. Mon. Wea. Rev., 138(4), 1172–1185.|
|Chan, S. C., Misra, V., & Smith, H. (2011). A modeling study of the interaction between the Atlantic Warm Pool, the tropical Atlantic easterlies, and the Lesser Antilles: ATLANTIC WARM POOL, EASTERLIES, ISLANDS INTERACTIONS. J. Geophys. Res., 116(D21).|
|DiNapoli, S. M., & Misra, V. (2012). Reconstructing the 20th century high-resolution climate of the southeastern United States. J. Geophys. Res., 117(D19), n/a-n/a.|
|Frumkin, A., & Misra, V. (2013). Predictability of dry season reforecasts over the tropical and the sub-tropical South American region. Int. J. Climatol., 33(5), 1237–1247.|
|Glazer, R. H., & Misra, V. (2018). Ice versus liquid water saturation in simulations of the Indian summer monsoon. Climate Dynamics, .|
|Groenen, D., & Misra, V. (2016). Characterization of the Rainy Season of Mesoamerica.. American Meteorological Society.|
Karmakar, N., & Misra, V. (2019). The Relation of Intraseasonal Variations With Local Onset and Demise of the Indian Summer Monsoon. J. Geophys. Res. Atmos., 124(5), 2483–2506.
Abstract: Two of the most important hydroclimatic features of the Indian Summer Monsoon (ISM) rainfall are its onset/demise and Intraseasonal Oscillations (ISOs) manifested by the active‐break cycles. In this study, we aim to understand the quantitative association between these two phenomena. An objective definition of local onset/demise of the ISM based on more than a century‐long India Meteorological Department (IMD) rain‐gauge observation is taken into consideration. Using multichannel singular spectrum analysis (MSSA) we isolate northward propagating low‐ (20–60 days; LF‐ISO) and northwestward propagating high‐ (10–20 days; HF‐ISO) frequency ISOs from the daily ISM rainfall. Our results suggest that a large number of local onset (59%) and demise (62%) events occur during positive developing phases and positive decaying phases of two ISOs, respectively, with phase‐locking between LF‐ISO and HF‐ISO being particularly important. Local onset is largely associated with favorable phases of ISOs across India except for LF‐ISO over eastern India and HF‐ISO over western Ghats and central India (CI). We find that local demise is more coherent with the ISO phases, especially with HF‐ISO across the domain. We performed a case study to understand large‐scale association with the onset of the ISM over CI. In 44 of total 58 cases (1948–2005), when CI onset occurred during favorable LF‐ISO or HF‐ISO phase, they are either linked with a northward propagation of convection from the equator in LF‐ISO timescale (28 cases) or westward propagating structures from the western Pacific in HF‐ISO timescale (27 cases).
Keywords: hydroclimatic, Indian Summer Monsoon, Intraseasonal Oscillations, eastern Indiawestward propagating
Karmakar, N., & Misra, V. (2019). Differences in Northward Propagation of Convection Over the Arabian Sea and Bay of Bengal During Boreal Summer. J. Geophys. Res. Atmos., 125(3).
Abstract: The governing dynamics that modulate the propagation characteristics of intraseasonal oscillations (ISO) during summer monsoon over the two ocean basins, Bay of Bengal (BoB) and Arabian Sea (AS), are investigated using observational analysis and high‐resolution regional coupled ocean‐atmosphere climate model simulations. ISO features are extracted over the Indian region using a data‐adaptive spectral method called multichannel singular spectrum analysis. ISO exhibits stronger intensity over the BoB than over the AS. But ISO‐filtered rainfall propagates at a faster rate ( urn:x-wiley:jgrd:media:jgrd55983:jgrd55983-math-00011.25°/day) over AS as compared to BoB ( urn:x-wiley:jgrd:media:jgrd55983:jgrd55983-math-0002.74°/day), giving rise to a northwest‐southeast tilted band of rainfall anomalies. However, the composite diagrams of several atmospheric fields associated with northward propagation like vorticity, low‐level convergence, and oceanic variables like sea surface temperature and mixed layer depth do not show this difference in propagation speed and all exhibit a speed of nearly 0.75°/day in both the ocean basins. The difference in speed of ISO‐filtered rainfall is explained through moisture flux convergence. Anomalous horizontal moisture advection plays a major role over AS in preconditioning the atmosphere and making it favorable for convection. Anomalous wind acting on climatological moisture gradient is the dominant term in the moisture advection equation. Easterly wind anomalies associated with a low‐level anticyclone over India helps advect moisture from the eastern side of the domain. The northwest‐southeast tilt of ISO is dictated by the atmospheric processes of moisture advection with the upper ocean playing a more passive role in causing the tilt.
Kim, D., Lee, S. - K., Lopez, H., Foltz, G. R., Misra, V., & Kumar, A. (2020). On the Role of Pacific-Atlantic SST Contrast and Associated Caribbean Sea Convection in August-October U.S. Regional Rainfall Variability. Geophys. Res. Lett., 47(11).
Abstract: This study investigates the large‐scale atmospheric processes that lead to U.S. precipitation variability in late summer to midfall (August–October; ASO) and shows that the well‐recognized relationship between North Atlantic Subtropical High and U.S. precipitation in peak summer (June–August) significantly weakens in ASO. The working hypothesis derived from our analysis is that in ASO convective activity in the Caribbean Sea, modulated by the tropical Pacific‐Atlantic sea surface temperature (SST) anomaly contrast, directly influences the North American Low‐Level Jet and thus U.S. precipitation east of the Rockies, through a Gill‐type response. This hypothesis derived from observations is strongly supported by a long‐term climate model simulation and by a linear baroclinic atmospheric model with prescribed diabatic forcings in the Caribbean Sea. This study integrates key findings from previous studies and advances a consistent physical rationale that links the Pacific‐Atlantic SST anomaly contrast, Caribbean Sea convective activity, and U.S. rainfall in ASO.
Keywords: Pacific‐ Atlantic SST interaction; Atlantic Warm pool; Caribbean Sea; U.S. precipitation