There is an observational evidence that the variability in the global upper-tropospheric flow fields on a monthly basis is dominated by a zonally uniform pattern symmetric about the equator. This fluctuation is characterized by the zonal mean zonal wind anomaly having the same sign within the Tropics, and thus has been related to changes in the global atmospheric angular momentum. In this paper...

precipitation data is of utmost importance to carry out many hydro-meteorological studies. observed warming over several decades has been linked to changes in the large-scale hydrological cycle such as: increasing atmospheric water vapour content, changing precipitation patterns, intensity and extremes, reduced snow cover and widespread melting of ice, and changes in soil moisture and runoff. p...

Observing trends in global ecosystem dynamics is an important first step, but attributing these trends to climate variability represents a further step in understanding Earth system changes. In the present study, we classified global Ecosystem Response Types (ERTs) based on common spatio-temporal patterns in time-series of Standardized Precipitation Evapotranspiration Index (SPEI) and FPAR3g an...

[1] At 2.7 million years ago the warm equable climates of early and ‘‘middle’’ Pliocene time (used here to mean from 5 to 2.7 Ma) were replaced by recurring ice ages. Most attempts to explain the change appeal either to changes in CO2 in the atmosphere or reduced heat transport by the Atlantic Ocean. The sources of the strongest teleconnections in the current climate, however, lie in the tropic...

Anomalies of precipitation, cloud, thermodynamic, and radiation variables are analyzed on the large spatial scale defined by the tropical oceans. In particular, relationships between the mean tropical oceanic precipitation anomaly and radiative anomalies are examined. It is found that tropical mean precipitation is well correlated with cloud properties and radiative fields. In particular, the t...

The aim of this study was to classify the most frequently observed atmospheric circulation anomaly patterns in eastern Africa and the adjacent Indian Ocean. As an example of the usefulness of such a classification, the second objective was to test whether these patterns account for intraseasonal rainfall anomalies in the region. A partitioning algorithm, known as dynamical cluster analysis, was...

The authors argue for the hypothesis that interactive feedbacks involving surface enthalpy fluxes are important to the dynamics of tropical intraseasonal variability. These include cloud-radiative feedbacks as well as surface turbulent flux feedbacks; the former effectively act to transport enthalpy from the ocean to the atmosphere, as do the latter. Evidence in favor of this hypothesis include...

The subseasonal variability of the extratropical large-scale atmospheric flow is characterized by recurrent or quasi-stationary circulation anomalies, termed weather regimes. Despite usefulness these regimes in numerous meteorological and socioeconomic applications, there an ongoing debate as to whether they represent physical modes atmosphere, are merely useful statistical categorizations. Her...

Upper ocean variations across the tropical Atlantic are strongly seasonal due to corresponding seasonality in surface forcing and continental runoff. This implies that many features regional upper state or transport anomalies may also be seasonally locked. In boreal summer autumn, remote sensing sea salinity (SSS) observations show presence of eastward propagating concurrent with development fr...

[1] The relationships among the boreal spring Southern Hemisphere Annular Mode (SAM), the Indian Ocean (IO) sea surface temperature (SST), and East Asian summer monsoon (EASM) are examined statistically in this paper. The variability of boreal spring SAM is closely related to the IO SST. When the SAM is in its strong positive phase in boreal spring, with low-pressure anomalies over the south po...