[1] The impacts of inter-El Niño events on South American circulation during austral summer are investigated using observations and an atmospheric general circulation model (AGCM). The AGCM was forced with sea surface temperature (SST) anomalies in the tropical Pacific for the two El Niño events of 1997/1998 (EN97) and 2002/2003 (EN02). The strong eastern Pacific SST anomaly of EN97 resulted in...

A simple multilayer-zonally symmetric model, using a multicloud convective parameterization and coupled to a dynamical bulk atmospheric boundary layer, is used here to simulate boreal summer intra-seasonal oscillations (BSISO) in the summer monsoon trough and elucidate the underlying main physical mechanisms responsible for their initiation, propagation, and termination. Northward-moving precip...

Climate change and water availability in the Middle East are important in understanding human adaptive capacities in the face of long-term environmental changes. The key role of water availability for sedentary and nomad populations in these arid to semiarid landscapes is understood, but the millennium-scale influence of hydrologic instability on vegetation dynamics, human occupation, and histo...

This work evaluates the potential for drought detection of the Fraction of Absorbed Photosynthetically Active Radiation (fAPAR) estimations operationally produced by the European Space Agency (ESA) as the Medium Resolution Imaging Spectroradiometer (MERIS) Level 2 Land Product. MERIS fAPAR daily data were used to produce 10-day time composites. The selected study area was the Iberia Peninsula. ...

[1] Observational analysis and model experiments show that the sea surface temperature anomaly associated with the Indian Ocean Basin mode (IOBM), which persists from spring to summer, can generate significant circumglobal teleconnection (CGT) in the Northern Hemisphere summer midlatitude atmosphere. A warm IOBM can induce a new atmospheric heating source in the south Asia through a positive fe...

Tree-ring-based reconstructions of the Palmer drought severity index (PDSI) indicate that, during the Medieval Climate Anomaly (MCA), the central plains of North America experienced recurrent periods of drought spanning decades or longer. These megadroughts had exceptional persistence compared to more recent events, but the causes remain uncertain. The authors conducted a suite of general circu...

The influence of phase and amplitude Indian Ocean Dipole (IOD) El Niño Southern Oscillation (ENSO) on the interannual variability summer monsoon rainfall (ISMR) over North East India (NEI) has been studied first time from 1960 to 2015. independent contribution different phases IOD ENSO in variabilities ISMR NEI is explained by correlation found that precipitation decreases due anomalous wind ve...

Atmospheric water vapour is an essential ingredient of weather and climate. The key features of its distribution can be represented by kinematic models which treat it as a passive scalar advected by a prescribed flow and reacting through condensation. Condensation acts as a sink that maintains specific humidity below a prescribed, space-dependent saturation value. To investigate how the interpl...

A suite of climate data sets andmultiple representations of atmosphericmoisture demand are used to calculate many estimates of the self-calibrated Palmer Drought Severity Index, a proxy for near-surface soil moisture, across California from 1901 to 2014 at high spatial resolution. Based on the ensemble of calculations, California drought conditions were record breaking in 2014, but probably not...

Multiple paleoclimate proxies are required for robust assessment of past hydroclimatic conditions. Currently, estimates of drought variability over the past several thousand years are based largely on tree-ring records. We produced a 1,500-y record of winter precipitation in the Pacific Northwest using a physical model-based analysis of lake sediment oxygen isotope data. Our results indicate th...