Evaluate the use of models for predicting future global warming [9 marks]

Indicative Content	Guidance
Explanation of models: Models simplify natural systems → enables predictions → based on historical data Climate models → used by scientists/Intergovernmental Panel on Climate Change → predict future climate change Strengths: Enhanced understanding of complex environmental relationships Identification of vulnerable regions → e.g. poles vs tropics Provides scenarios for policy decisions Predictions based on extensive historical data → enhances reliability Provides clear data on controversial issues Allows visualisation of projected effects → e.g. for global temperature changes Limitations: Inaccuracy of predictions → detailed data only collected relatively recently Models assume climate factors will behave as in the past → may not always hold true Conflicting results from different models → creates uncertainty Politicians/leaders exploit model variations to support agendas Simplifications/approximations introduce uncertainties Limited understanding of statistical limitations of models by non-experts Inconsistent data sources and methodologies → e.g. use of different equipment/techniques	You will always have to answer two 9 mark questions from Section B in your IB ESS SL Paper 2 exam This is a 'level of response' answer. The examiner will award you a combined mark out of 9 for knowledge, application, analysis and evaluation ‘Evaluate’ (for 9 marks) requires: Knowledge of concepts, principles and models Application to the context using relevant and focused examples Analysis showing logical and coherent chains of reasoning of a range of issues Evaluation showing critical thinking linked to the context Depth is more important than breadth It is sensible to discuss two or three strengths and weaknesses and to apply them in detail For top-level evaluation, informed judgement is required This can be demonstrated in a conclusion that synthesises and weighs up the arguments to form a supported answer to the question
Model Answer
The use of models for predicting future global warming plays a vital role in climate science and policy-making. Models are simplified representations of complex natural systems, enabling predictions of climate change based on historical climate data [K]. Climate models, powered by mathematical formulae and computer programs, are valuable tools for scientists and organisations like the IPCC to forecast future changes in climate patterns [An]. One strength of these models is that they can provide a range of scenarios and predictions for policy and decision-makers. By using extensive historical climate data, these models can provide a certain level of statistical certainty in their projections. These model predictions allow for objective discussions and decision-making on environmental issues that can be controversial and politically-charged [An]. Models also contribute to a greater understanding of the intricate relationships between various environmental factors and have revealed that certain regions, such as polar areas, may be more vulnerable to temperature increases compared to others, such as the tropics [Ap]. However, these models also have many limitations [E]. Contrasting results from different models can introduce uncertainty and confusion among policymakers and the public. Politicians may exploit these differences between models to support their specific agendas, leading to biased decision-making [Ap]. Models rely on approximations and simplifications to make predictions, introducing further uncertainty, and model inputs can be limiting as comprehensive climate recordings only began relatively recently. Lastly, data sources and measurement methodologies used to collect climate data often differ greatly between regions, which can make data inconsistent or incompatible, further complicating the modelling process [An]. In conclusion, while climate models are powerful tools for predicting future global warming and helping to inform decision-making, they are not without their limitations. The strength of these models lies in their ability to provide detailed future climate scenarios and objective information on how global temperatures are likely to change in the future [E]. However, due to the limitations of these models, such as conflicting results, political manipulation, and their heavy reliance on historical data that may be lacking in detail or reliability, caution is required when using these models for decision-making in the face of the current climate emergency [E].
Commentary
This answer is an example - yours may be different The answer discusses both strengths and weaknesses of models, and finishes with a supported final judgement The overall effectiveness of using models is evaluated in the concluding paragraph The response is annotated to show where the skills of knowledge (K), application (Ap), analysis (An) and evaluation (E) have been demonstrated

Systems & Models (SL IB Environmental Systems & Societies (ESS))

Topic Questions