The conclusion is not just a summary, although it can be useful to recap on key points. You should return to the question and say what you think the answer is, based on the evidence that you have presented. Frequently, the answer will be ‘it depends’ but be careful about sitting on the fence. Express a strong, justified point of view: this can be difficult in physical geography, but there is often room to speculate on future developments, for example, or to place the answer in the context of a wider geographical issue.
Conclusions can be difficult to write. They are not just a summary: they should draw your argument together. The following text is a neat concluding paragraph that: a) provides an answer to the question; b) acknowledges the complexity of the debate without recapitulating the whole argument in detail; and c) introduces a ‘twist’ (i.e., anthropogenic impacts) that demonstrate the author has a grasp on the wider context of the question.
Q: Climate change during the Quaternary has been mainly driven by variability in Earth’s orbit. Discuss
In conclusion, the evidence provided in this essay, explaining the strong correlation between the periodicities of Milankovitch cycles with the periodicity of glacial and interglacial periods over the past nearly three million years, suggests that climate change during the Quaternary has been mainly driven by variability in Earth’s orbit. Similarly the lack of support for most secondary explanations would suggest that orbital forcing has certainly been the primary factor forcing the climate. However, as discussed, there are still uncertainties and problems with this hypothesis, primarily to do with the 100,000 year eccentricity cycle, and doubts as to whether this cycle could produce the corresponding climatic cycle by direct forcing. Also, as seen by examining recent anthropogenically-induced global warming, it is possible to see that natural factors are not the only factor playing a role in affecting the climate, and it is still uncertain as to what the effects of anthropogenic activity will be into the future, but it may be able to induce global climate change on a large scale.
Activity: Comparing conclusions
The following examples all conclude essays responding to the question:
Explain the processes which drive global ocean circulation and discuss its relationship with meridional temperature distribution
What are the benefits and drawbacks of each text?
In conclusion, the global ocean circulation is driven by a number of interacting processes. Surface waters and currents are driven predominantly by the force of the wind that once deflected by the Coriolis effect produces large circulations in each of the ocean’s basins. Especially in the northern hemisphere, predominantly due to the continental configuration, these gyres possess strong poleward westerly boundary currents that are highly effective in the redistribution of warmer water to the colder Polar Regions. Similarly the occurrence of these strong boundary flows enables the formation of eddies, which are smaller enclosed regions of warmer water in the North Atlantic that also encourage the transfer of heat poleward. Deep water flows in the ocean are driven by density gradients resulting from temperature and salinity differences and together the deep water and surface currents provide a ‘conveyor belt’ system that can transfers water across latitudes, aiming to even out the uneven meridional temperature distribution. Polewards heat transport takes place in both the atmosphere and the oceans (with the atmosphere accounting for around two thirds and the oceans one third of the transport (Barry and Chorley, 2003)) however as the oceans have a higher inertia, they are a more long term store and transport of heat and therefore have a critical influence in the meridional temperature distribution.
During the past few years, an increasing number of studies have paid attention to these complex climatic processes (such as El Niño, monsoons, or present climate change), and it has become more and more evident that oceans are in fact heavily related to apparently unlinked processes: as a result, ocean currents are no longer considered interesting exclusively for navigational purposes; however, there is much work to be done, especially in the thermohaline circulation field, if we really are to understand completely the way in which ocean circulation works.
The scale and complexity of the global ocean circulation system cannot be overestimated. With its interaction with atmospheric circulation in exchanging energy at the interface between them, the oceans redistribute energy at a scale which could not be done by humanity. Interactions with changing surfaces and outside conditions such as changes in winds and solar insolation inevitably produce fluctuations in the efficiency and extent of overall meridional heat energy distribution. Along with the atmosphere and the air cells produced via heat and air pressure gradients the oceans provide the overall stability and pattern of temperature distributions without which climatic conditions would in no way parallel the conditions we see today.
Now click here to access feedback on each of the three conclusions above.