When might the Arctic be nearly ice-free in September?

AA SLAA HLAI SLAI HL Solid Also in: Modelling, Statistics

Research question

Which models (linear, quadratic, exponential) best fit the September Arctic sea-ice extent since 1979, and how widely do their predictions of when extent falls below 1 million km² disagree?

Adapt it: change the place, the data or the comparison until the question is yours.

Why it makes a good exploration

“Ice-free Arctic” predictions make headlines, often without uncertainty. Showing how much the answer depends on the model — with NSIDC's official data — is an IA about the limits of extrapolation.

The mathematics you'll need

Linear, quadratic and exponential models
Residual analysis and R²
Solving model equations for a threshold
Discussing uncertainty in extrapolation

Course labels show where a technique sits; using maths from outside your course is fine if you explain it clearly and say it is new to you.

Where the data comes from

Download monthly extent (September values) from the NSIDC Sea Ice Index.

NSIDC Sea Ice Index — Daily and monthly Arctic and Antarctic sea-ice extent since 1978, CSV.

Cite every source in a footnote where you use it and in your bibliography. Check the licence of any dataset you download.

A possible outline

Explain what extent measures and the 1 million km² threshold.
Fit several models.
Solve each for the threshold year.
Test models on the most recent years.
Reflect on why the models disagree so much.

Pitfalls that cost marks

Presenting one model's year as a prediction.
Using daily data without averaging.
Ignoring year-to-year variability.

Showing personal engagement

Compare your range with published scientific estimates (cite them).
Look at March maxima as well.
Discuss what the answer means for people living in the Arctic.

See Criterion C: personal engagement for what examiners look for.

Taking it further

Fit models on data up to 2012 (a record low) and see how badly they predicted later years.

Turn this idea into your IA

Plan this IAOpens the planner with this question, the maths and data sources filled in. Desmos workspacePlot your data, fit models and keep your graphs with your plan. AI feedback on a draftCriterion-by-criterion feedback with evidence from your own text. Coaching, not rewriting. Examiner reviewPete, a practising IA examiner, reads your draft and talks it through with you (€100).