Transient temperature and sea level response of a two-dimensional ocean-climate model to greenhouse gas increases
- Univ. of Toronto, Ontario (Canada)
A two-dimensional dynamical ocean model is coupled to an energy balance climate model and used to investigate the transient surface temperature and sea level response to greenhouse gas increases. For most experiments a step function surface-troposphere heating perturbation of 6 W/sq m is applied. A transient reduction in the thermohaline overturning flux of 15-30% occurs in most experiments, although in some cases a near-total circulation collapse occurs within the first 100 years and lasts 700-1000 years. The transient circulation decrease is attributed to the greater rate of downward penetration of the heating anomaly in downwelling rather than in upwelling regions and is not a result of reduced convection. For experiments in which the steady state circulation is qualitatively unchanged after a heating perturbation, the surface temperature response is roughly uniform with latitude, in the absence of ice and snow. However, in some cases a heating perturbation induces the transition from a one-cell to a two-cell overturning circulation, or causes a complete reversal in the direction of overturning when a single cell spans both hemispheres, causing marked latitudinal variations in the surface temperature response.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 85443
- Journal Information:
- Journal of Geophysical Research, Vol. 99, Issue C9; Other Information: PBD: Sep 1994
- Country of Publication:
- United States
- Language:
- English
Similar Records
Century-scale variability in a randomly forced, two-dimensional thermohaline ocean circulation model
Documentation, critique, and suggested changes in a simple ocean model