Development Log

Written and conceived by Matt Lloyd 2018


Climate Change - some data

- 10th of September, 2019

Climate Change - some data

Good Day,

This day, morning - afternoon - I trawled through Bureau of Meterology data for a number of weather stations around the country to collate some data to view the change in temperature across the continent of Australia from North to South.

Given the Earth is a spherical object there are latitudes measured in degrees from the equator that represent how far North or South each location is.

The closest to the equator, hence warmest, location I chose was Cairns - at about 16 degrees South of the equator.

The furthest from the equator was in Tasmania at approximately 42 degrees South of the equator - noting that Antarctica is about 90 degrees South of the equator.

The temperature metric used was as follows for each weather station (4) along the point:

Minimum overnight temperature per day recorded at each weather station, compared to the average minimum yearly temperature for the year 2018 at that weather station.

This minimum temperature was then counted as a percentage of the total days collected at each weather station for a series of 12 years, 1945 to 1950 and 2013 to 2018.

The method used was to count how often the temperature dipped below this mean temperature and record the frequency.

The idea being that if the global temperatures are warming over time then one would expect that - with heat being trapped by the atmosphere and discounting the sun's direct effects as much as possible - if the Earth is warming there would be less days below the average minimum temperature as the years go along.

I have shown the summary data and graph for this below:

Figure 1.

The primary conclusion we can make from this data is as follows:

2013 to 2018 in all states had less 'cool nights' than it did between '1945 to 1950' at those weather stations.

Does this mean the temperature is warming?

A first thought would be yes.

Is this outside of expected variation - my data does not show this at all - it merely reports two sets of yearly figures - 50-60 years apart.

However - a notable fact is that the number of cool days decreased in all states, at all latitudes, across the continent of Australia in these remote locations.

The assumption behind my idea is that with global warming minimum overnight temperatures will not reduce as far as one would expect over the course of a year if the atmosphere was holding in heat.

So....Primary Conclusion

There were less 'cool nights' all over the country 60 years after the 1945-1950.

This implies warming - but without additional data is not possible for me from this set to actually conclude that - but it is a beginning of course.