Contemporary Climate Change 
6.8.3. When Will Attribution Occur?
The fact that the cause (the enhanced greenhouse effect) and effect (global warming) have not unambiguously been linked leads to the question: when is this [attribution] likely to occur? Detection is not a simple yes/no issue. Rather, it involves the gradual accumulation of observational evidence in support of model predictions. The scientist's task is to reduce the uncertainties associated with the understanding of the climate system. Thus, while the ultimate objective of climate research is detection, it is really the climate sensitivity (section 2.8) one is interested in. A better understanding of this key parameter will not only allow one to argue with increased confidence that anthropogenic global warming is (or is not) occurring, but it will support prediction of future climate change, both anthropogenic and natural.
Figure 6.14 illustrates how the uncertainty in the climate sensitivity puts constraints on the timing of the detection issue. GCMs indicate that the climate sensitivity (the CO2 doubling temperature) lies in the region 1.5 to 4.5°C. A high climate sensitivity will allow detection
before 2010. Conversely, if it is low, detection may not occur for another 50 years.
Greenhouse Gases
-Carbon Dioxide
·Sources
·Sinks
·Carbon Cycle
·Concentrations
·Equilibrium
-Methane
·Sources
·Sinks
·Concentrations
-Nitrous Oxide
·Sources
·Sinks
·Concentrations
-Halocarbons
·Sources
·Sinks
·Concentrations
-Ozone
-Other Gases
-Lifetimes
-Summary
Greenhouse Forcing
-Forcing Factors
-GWPs
-ΔF-ΔC
-1765 to 1990
-Ozone
Aerosols
-Sources & Sinks
-Forcing
·Direct
·Indirect
-Total Forcing
Climate Variations
-Surface Temp.
-Precipitation
-Other
·Stratosphere
·Cryosphere
·Atmos. Circulation
·Cloudiness
Detection
-Modelling
-Attribution
·Latitudes.
·Stratosphere
·Precipitation
·Sea Level
·Fingerprints
-When?
Future Climate
-GCM Simulations
-Feedbacks
·Water Vapour
·Clouds
·Ice Albedo
·G-house Gases
-21st Century
Impacts
-Agriculture
-Forestry
-Ecosystems
-Water Resources
-Oceans/Coasts
-Human & Health
Responses
-Stabilising
-FCCC
-Kyoto Protocol
-UK Programme
·Energy Demand
·Energy Supply
-Evaluation