Describing the global pattern
Describe and explain are different jobs
- Describing says what the arrangement looks like. Explaining says what made it. They are marked separately, and mixing them leaves both looking thin.
- A description contains no "because". The moment you write because, you have moved to part 2.
- Write the description first and finish it. A description assembled in fragments between explanations is almost never complete.
- The description is where Merit is usually won, because Merit asks for it in detail — and detail in a global description means named places, directions, extents and figures.
The five-part description that works for any global pattern
- Part 1 — the overall statement. One sentence naming the arrangement. Earthquakes and volcanoes are concentrated in narrow, mostly linear belts rather than spread evenly.
- Part 2 — where the concentrations are. Name them, and name the places they run through. The circum-Pacific belt runs from New Zealand through Tonga, Papua New Guinea, the Philippines, Japan and Kamchatka, across to Alaska and down through the western United States, Mexico, Central America, and the Andes to southern Chile.
- Part 3 — where it is absent. This is the part students skip, and it is often the most convincing. Almost no activity occurs in the interiors of Australia, Africa north of the Rift, Canada, Siberia, Brazil or Antarctica.
- Part 4 — the shape and the scale. The belts are linear and narrow — typically tens to a few hundred kilometres wide — but thousands of kilometres long.
- Part 5 — the exceptions. Hawai
i and Iceland do not fit: Hawaii sits in the middle of a plate, and Iceland sits on a ridge that has risen above sea level.
Absence is evidence, and so are exceptions
- A pattern is defined as much by where something is not as by where it is. Saying that continental interiors are almost inactive tells a reader that the cause must be at the edges of something, which is most of the way to part 2.
- State the exceptions rather than hiding them. Hawai`i is thousands of kilometres from any boundary, and it is volcanically active. Naming it, and saying it needs a separate explanation, is a mark of a good description, not an admission of weakness.
- A description with no exceptions is usually a description that has not looked hard enough. Almost every real global pattern has some, and markers know it.
- Do not let exceptions take over. One or two sentences: name them, say they do not fit, and move on. The full explanation belongs in part 2.
Using geographic terminology
- At Level 2, Achieved allows plain description. You do not have to use technical terms to pass, and clear plain English beats misused jargon every time. (At Level 3, AS91432 does require terminology at Achieved — so if you go on to Level 3, this is one of the things that changes.)
- Terminology still helps at Merit and Excellence, because it is more precise and therefore more detailed. Useful terms here: distribution, linear, belt, concentrated, dispersed, hemisphere, latitude, boundary, subduction, rift.
- Use direction and extent properly. In the north-west of the Pacific basin is more useful than up there, and between about 30 and 45 degrees south is more useful than quite far south.
- Every term you use, use correctly. A misapplied term costs more than the plain word it replaced.
Making the map do the work
- A sketch map is the fastest way to describe a global pattern in detail, and it lets your text spend its words on the parts a map cannot show.
- What the map must carry: a title, a key, labelled belts or regions, and a note of your source. A world map with unlabelled shading describes nothing.
- Draw the belts generalised, and say that you have. A hand-drawn belt is a schematic, not a data map, and labelling it as one is honest and costs nothing.
- Refer to the map from the text. As the map shows, the belt is continuous around the Pacific except for a break in the south-east ties the two together; a map nobody mentions is decoration.
Worked Example
Worked example
A student's first attempt at part 1 reads:
Rewrite it to Merit standard.
Answer:
Step 1 — diagnose. This is a list with no arrangement. Nobody could draw it. There is no statement of shape, no absence, no extent, no figure, and some places have more than others is a description of every distribution ever measured.
Step 2 — write the overall statement. What is the arrangement, in one checkable sentence?
Earthquakes and volcanoes are concentrated in narrow, mostly linear belts rather than spread evenly across the Earth's surface.
Step 3 — name the concentrations and trace each one in order. Not a list of countries — a route.
Step 4 — add the absences. Where is there almost nothing?
Step 5 — add scale, and one figure with a source type.
Step 6 — add the exceptions, briefly.
The rewrite:
The rewrite states the arrangement in one sentence, traces each belt as a route rather than listing countries, names the absences, gives width and length, attaches one quantified figure with its source type and an approximation warning, and names the exceptions without trying to explain them.