Skip to main content

CLIMBER-2: a climate system model of intermediate complexity. Part II: model sensitivity


 A set of sensitivity experiments with the climate system model of intermediate complexity CLIMBER-2 was performed to compare its sensitivity to changes in different types of forcings and boundary conditions with the results of comprehensive models (GCMs). We investigated the climate system response to changes in freshwater flux into the Northern Atlantic, CO2 concentration, solar insolation, and vegetation cover in the boreal zone and in the tropics. All these experiments were compared with the results of corresponding experiments performed with different GCMs. Qualitative, and in many respects, quantitative agreement between the results of CLIMBER-2 and GCMs demonstrate the ability of our climate system model of intermediate complexity to address diverse aspects of the climate change problem. In addition, we used our model for a series of experiments to assess the impact of some climate feedbacks and uncertainties in model parameters on the model sensitivity to different forcings. We studied the role of freshwater feedback and vertical ocean diffusivity for the stability properties of the thermohaline ocean circulation. We show that freshwater feedback plays a minor role, while changes of vertical diffusivity in the ocean considerably affect the circulation stability. In global warming experiments we analysed the impact of hydrological sensitivity and vertical diffusivity on the long-term evolution of the thermohaline circulation. In the boreal and tropical deforestation experiments we assessed the role of an interactive ocean and showed that for both types of deforestation scenarios, an interactive ocean leads to an additional cooling due to albedo and water vapour feedbacks.

This is a preview of subscription content, access via your institution.

Author information

Authors and Affiliations


Additional information

Received: 28 May 2000 / Accepted: 9 November 2000

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Ganopolski, A., Petoukhov, V., Rahmstorf, S. et al. CLIMBER-2: a climate system model of intermediate complexity. Part II: model sensitivity. Climate Dynamics 17, 735–751 (2001).

Download citation

  • Issue Date:

  • DOI:


  • Intermediate Complexity
  • Vertical Diffusivity
  • Freshwater Flux
  • Climate System Model
  • Interactive Ocean