Copy and complete the following table showing each variable’s data type and a suitable range of values that would represent the information shown above.

Using the rules and initial values above, construct the pseudocode that would enable the area of the sea ice and the sea level rise to be calculated if there was an increase of 0.04 °C in the ocean surface temperature.

Using the information above state the area of the sea ice.

Using the information above state the change in sea level.

Using the formula, rules and initial data given above, construct the pseudocode that would calculate the year that the area of sea ice will be less than 10 000 km².

Identify two ways that this model could be implemented.

Explain why the accuracy of the simulation in predicting the area of the sea ice is critical.

Award [3 max].

Award [4 max]. 
Initialization – Original area of sea ice;
Initialization – Surface temperature change;
New sea ice area calculation;
Sea level change calculation;

Example algorithm:

OriginalSeaIceArea = 1000000
SurfaceTempChange = 0.04
NewSeaIceArea = OriginalSeaIceArea * (1 – SurfaceTempChange)
SeaLevelChange = -(NewSeaIceArea - OriginalSeaIceArea) / OriginalSeaIceArea * 100 * 20

Award [1 max].
960 000 (km²);

Award [1 max].
80 (mm);

Award [7 max].
Initialization – Initial areas of Ice and water, and starting year;
Use of loop;
Loop parameters (limits, condition, increment, end statement correct);
Average albedo;
Rate of decrease calculation;
Area of ice update calculation;
Area of open water update calculation;
Output;

Example algorithm:

IceArea = 1000000
OpenArea = 1000000
Year = 2019
Loop While IceArea > 10000
   TotalArea = IceArea + OpenArea
   AveAlbedo = ((IceArea * 0.6) + (OpenArea * 0.1)) / (IceArea + OpenArea)
   Decrease = 0.3 / (AveAlbedo * AveAlbedo)
   // allow Decrease = 0.3 / AveAlbedo ^ 2
   IceArea = IceArea * (1 − (0.01 * Decrease))
   OpenArea = TotalArea − IceArea
   Year = Year + 2
End loop
Output "Date when there less than 10 000km2 of ice in the ocean 
is " Year

Award [2 max].
Spreadsheets;
IDEs using code;

Award [3 max].
If the calculation of the rate of reduction of the sea ice is inaccurate the calculation of the amount of sea ice remaining;
At a given time will turn out to be wrong;
So, work to correct the problems may be too little/too great;
The year in which the sea ice is predicted to be 10 000 km²;
Will be wrong;
So, ice coverage may be more/less than expected in the calculated year;

Most candidates recognized this as a straightforward question. However, some candidates were unable to demonstrate the concept of data types and range of values for given variables.

This question was reasonably well answered and most candidates were able to produce some pseudocode. However, a few candidates struggled to apply all the required formulae and couldn’t produce all the required values.

The question was answered correctly by most of the candidates.

The question was answered correctly by most of the candidates.

The vast majority of candidates could not produce the correct pseudocode to calculate all the required values.

The skill to apply a loop in this question was poorly demonstrated by most of the candidates.

The question was not well understood by the majority of the candidates. Most of the responses were generic and off course.

Most candidates did not answer the question appropriately and focused more on generic points rather than being specific to the scenario.