Wilma C. Hazeleger

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[1] Interannual variability associated with the zonal and the meridional mode in the tropical Atlantic is studied in nine coupled ocean – atmosphere models for twentieth century climate conditions (TC) and the SRES-A1B scenario for future greenhouse gas concentrations. For TC, the subtropical part of the meridional mode is reasonably well simulated, in(More)
The response of mode water formation to typical atmospheric forcing anomalies is studied as a possible mechanism for generating the observed interannual to decadal variability in mode water. An isopycnal model of the North Atlantic subtropical gyre, coupled to a mixed layer model, is used for this purpose. Geometry and forcing are idealized. The control run(More)
Subduction is the process by which fluid transfers from the mixed layer to the interior of the ocean. South of the Gulf Stream extension, 18Њ mode water is formed in a region of high subduction rates. In this region there is high mesoscale eddy activity. In the present study the role of eddies in modifying the large-scale subduction into mode water is(More)
  • Ronald Van Haren, Geert, Jan Van Oldenborgh, Geert Lenderink, Matthew Collins, Wilco Hazeleger +6 others
  • 2011
Clear precipitation trends have been observed in Europe over the past century. In winter, precipitation has increased in northwestern Europe. In summer , there has been an increase along many coasts in the same area. Over the second half of the past century precipitation also decreased in southern Europe in winter. An investigation of precipitation trends(More)
  • Andreas Sterl, Jan Geert, Van Oldenborgh, Michiel Van Den Broeke, Gerrit Burgers, Bart Van Den Hurk +10 others
  • 2008
[1] In the Essence project a 17-member ensemble simulation of climate change in response to the SRES A1b scenario has been carried out using the ECHAM5/MPI-OM climate model. The relatively large size of the ensemble makes it possible to accurately investigate changes in extreme values of climate variables. Here we focus on the annual-maximum 2m-temperature(More)
  • Caroline A Katsman, A Sterl, J J Beersma, H W Van Den Brink, J A Church, W Hazeleger +19 others
  • 2009
Sea level rise, especially combined with possible changes in storm surges and increased river discharge resulting from climate change, poses a major threat in low-lying river deltas. In this study we focus on a specific example of such a delta: the Netherlands. To evaluate whether the country's flood protection strategy is capable of coping with future(More)
  • W.-P Breugem, P Chang, C J Jang, J Mignot, W Hazeleger
  • 2007
The Northwestern Tropical Atlantic (NwTA) is one of the regions in the tropical oceans where thick barrier layers (BLs) form during boreal fall and winter. Once formed, BLs tend to inhibit entrainment cooling of the mixed layer. Compared to observations, many coupled General Circulation Models (GCMs) misrepresent the dynamics of BLs. It is shown that this(More)
  • Wilco Hazeleger, W Hazeleger, Netherlands, Nl, Acknowledgments R Seager, A Clement +3 others
  • 2005
Tropical meridional ocean heat transport is studied in six coupled ocean-atmosphere models in which atmospheric CO 2 concentration has been increased. In the Indo-Pacific, the strength of Subtropical Cells (STCs) changes in response to changes in the trade winds. However, the change is not consistent among models. In contrast, in all models the tropical(More)
Ocean-atmosphere variability in the tropical Indian Ocean is investigated using observational data and ensemble experiments with a coupled general circulation model. In one ensemble (IO runs) the ocean-model domain is limited to the Indian Ocean and observed sea surface temperatures force the atmospheric model elsewhere. In a second ensemble (TPIO) the(More)
  • M K Van Der Molen, B J J M Van Den Hurk, W Hazeleger
  • 2011
In climate simulations we find a pronounced zonal gradient of climate response to land cover change. Climate response approaches zero in the tropics, and increases towards the poles. The zonal gradient in climate response to land cover change results from damping feedbacks in the tropics, rather than from polar amplification. The main cause for the damping(More)