Andrew T. Wittenberg

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  • Anand Gnanadesikan, Keith W Dixon, Stephen M Griffies, V Balaji, Marcelo Barreiro, J Anthony Beesley +23 others
  • 2006
The current generation of coupled climate models run at the Geophysical Fluid Dynamics Laboratory (GFDL) as part of the Climate Change Science Program contains ocean components that differ in almost every respect from those contained in previous generations of GFDL climate models. This paper summarizes the new physical features of the models and examines(More)
Since the mid-nineteenth century the Earth's surface has warmed, and models indicate that human activities have caused part of the warming by altering the radiative balance of the atmosphere. Simple theories suggest that global warming will reduce the strength of the mean tropical atmospheric circulation. An important aspect of this tropical circulation is(More)
Finding correlations among data is one of the most essential tasks in many scientific investigations and discoveries. This paper addresses the issue of creating a static volume classification that summarizes the correlation connection in time-varying multivariate data sets. In practice, computing all temporal and spatial correlations for large 3D(More)
We present a correlation study of time-varying multivariate volu-metric data sets. In most scientific disciplines, to test hypotheses and discover insights, scientists are interested in looking for connections among different variables, or among different spatial locations within a data field. In response, we propose a suite of techniques to analyze the(More)
Observations and climate simulations exhibit epochs of extreme El Ni~ no–Southern Oscillation (ENSO) behavior that can persist for decades. Previous studies have revealed a wide range of ENSO responses to forcings from greenhouse gases, aerosols, and orbital variations, but they have also shown that interdecadal modulation of ENSO can arise even without(More)
| independent days among the 184, i.e., a de-correlation time of about 10 days, which might, however, be a strong hypothesis in the case of persisting hot events involving long-memory processes such as soil moisture deficit. Conclusions. In conclusion, the record hot spring of 2012 over the eastern United States can be mainly explained by atmospheric(More)
Surface wind stresses are fundamental to understanding El Niño, yet most observational stress products are too short to permit multidecadal ENSO studies. Two exceptions are the Florida State University subjective analysis (FSU1) and the NCEP–NCAR reanalysis (NCEP1), which are widely used in climate research. Here, the focus is on the aspects of the stress(More)
(Delworth et al. 2006; Wittenberg et al. 2006), with external forcings held at 1860 values, spontaneously produces extreme ENSO epochs that can last decades, or even centuries (Wittenberg 2009; 20 centuries shown above). Epoch M7 resembles observed ENSO behavior during 1982-98, with strong, warm-skewed ENSO events five or more years apart. M2 resembles(More)
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