Today I learned something that almost had me in disbelief. This was purely by accident. I wrote a convenience web app that showed yesterday's temperature. But sometimes the data isn't available for the maximum from the previous day at 9am in the morning. So I thought, what about the daily readings from the weather stations. The didn't match. Two lots of data where the high and low from the previous day's data didn't match. How could this be?
I can explain this away since one lot of data is reported every 30 minutes. If these are spot measurements then the temperature at each minute, or even every second, could be higher or lower but we wouldn't know. So yes, it's easy for there to be a difference.
Then I read an article where a retired head master has an obvious special interest in the weather and followed through on why temperatures can spike quite a bit minute to minute. We're now in an age where we're using different measuring devices. Devices that can accurately measure temperature at a particular point in time. Ever walked through water at the beach an noticed how there's warmer spots and even areas that seem to flow with different temperatures. What's the temperature of the water? What's to say this isn't happening with measuring the air temperature. Instantaneous fluctuations. Yes the measurement isn't wrong, but to compare this type of measure with historical records where equipment by its nature averaged out the reading due to slower response times, can make for significant apparent changes that make the headlines.
The hottest overnight temperature on record. Or was it just because we're now measuring it differently? The headline grabbers don't highlight that we may be talking about a fraction of a degree. That doesn't make it as sensational.
This really plays into the hands of the climate change sceptics. If we can't trust the weather reporting then how can we trust what's being reported about climate change. Any scientist (or politician) going against climate change right now won't be treated seriously, or worse, they'll be treated very poorly.
This is one person's story I found interesting.
https://wattsupwiththat.com/2017/10/19/in-australia-faulty-bom-temperature-sensors-contribute-to-hottest-year-ever/
The issue isn't about whether the temperature is being measured correctly, but the time the measurements are averaged over. It appears the Bureau of Meteorology in Australia uses a single spot measurement each minute, whereas in the UK it is the average of the 60 measurements in the minute (one per second) and in the USA, it is the average over 5 minutes. There's nothing wrong with any of the approaches, but what is wrong is you can't compare if you measure things differently.
Another article I thought worth reading was how the historical temperatures in Darwin have been reduced using different approaches. Few people are experts in this area but for us laypeople, it just doesn't feel right to go back and reduce historical temperature values which then helps argue that global warming is occurring. That just puts doubt into people's mind. Doubt is all the climate change sceptics need to convince people climate change isn't happening. No science. Just doubt.
https://jennifermarohasy.com/2019/02/changes-to-darwins-climate-history-are-not-logical/
In this case, removing the earlier hot period from the data so it is outside the range for the trend just doesn't make sense. So often we see people who wish to prove their point only use a selection of data which proves their point, but ignores other data which does not help their case.
Now when I hear news items about the highest or lowest temperature for a day, month, period, I need to be aware of how much the change is. If that's not reported it's just sensationalist reporting designed to grab headlines and capture viewers attention.
The real sadness here is I do believe we are having a negative impact on our world. Just living, eating, consuming, travelling, all use resources. The more people the more resources. There has to be an impact and that impact just feels like it will be devastating. To not have a global standard by which all countries agree means it's far more difficult to do something globally and be in agreement.
What started as what appeared to be a very simple personal project, of what was yesterday's temperature, became far more complex. The good outcome however is if we just chill and relax, all that is really needed from yesterday's weather is a rough guide. A few degrees here or there doesn't really matter. We just want to know what yesterday's weather is so we can compare it to today. Is it going to be similar, hotter, or cooler? The answer doesn't need high precision.
Kelvin Eldridge
www.WeatherYesterday.com.au
PS. Unlike some sites this post is not meant to be a criticism of the Bureau of Meteorology. Weather is not an exact science. The resources provided by the BOM are used by most of us most days of the year and are appreciated. I have no idea if the actual historical raw data is being modified and I certainly hope it isn't. Modelling isn't the raw data, just someone's interpretation of the raw data, and that can and will change over time as technology and knowledge changes.
I can explain this away since one lot of data is reported every 30 minutes. If these are spot measurements then the temperature at each minute, or even every second, could be higher or lower but we wouldn't know. So yes, it's easy for there to be a difference.
Then I read an article where a retired head master has an obvious special interest in the weather and followed through on why temperatures can spike quite a bit minute to minute. We're now in an age where we're using different measuring devices. Devices that can accurately measure temperature at a particular point in time. Ever walked through water at the beach an noticed how there's warmer spots and even areas that seem to flow with different temperatures. What's the temperature of the water? What's to say this isn't happening with measuring the air temperature. Instantaneous fluctuations. Yes the measurement isn't wrong, but to compare this type of measure with historical records where equipment by its nature averaged out the reading due to slower response times, can make for significant apparent changes that make the headlines.
The hottest overnight temperature on record. Or was it just because we're now measuring it differently? The headline grabbers don't highlight that we may be talking about a fraction of a degree. That doesn't make it as sensational.
This really plays into the hands of the climate change sceptics. If we can't trust the weather reporting then how can we trust what's being reported about climate change. Any scientist (or politician) going against climate change right now won't be treated seriously, or worse, they'll be treated very poorly.
This is one person's story I found interesting.
https://wattsupwiththat.com/2017/10/19/in-australia-faulty-bom-temperature-sensors-contribute-to-hottest-year-ever/
The issue isn't about whether the temperature is being measured correctly, but the time the measurements are averaged over. It appears the Bureau of Meteorology in Australia uses a single spot measurement each minute, whereas in the UK it is the average of the 60 measurements in the minute (one per second) and in the USA, it is the average over 5 minutes. There's nothing wrong with any of the approaches, but what is wrong is you can't compare if you measure things differently.
Another article I thought worth reading was how the historical temperatures in Darwin have been reduced using different approaches. Few people are experts in this area but for us laypeople, it just doesn't feel right to go back and reduce historical temperature values which then helps argue that global warming is occurring. That just puts doubt into people's mind. Doubt is all the climate change sceptics need to convince people climate change isn't happening. No science. Just doubt.
https://jennifermarohasy.com/2019/02/changes-to-darwins-climate-history-are-not-logical/
In this case, removing the earlier hot period from the data so it is outside the range for the trend just doesn't make sense. So often we see people who wish to prove their point only use a selection of data which proves their point, but ignores other data which does not help their case.
Now when I hear news items about the highest or lowest temperature for a day, month, period, I need to be aware of how much the change is. If that's not reported it's just sensationalist reporting designed to grab headlines and capture viewers attention.
The real sadness here is I do believe we are having a negative impact on our world. Just living, eating, consuming, travelling, all use resources. The more people the more resources. There has to be an impact and that impact just feels like it will be devastating. To not have a global standard by which all countries agree means it's far more difficult to do something globally and be in agreement.
What started as what appeared to be a very simple personal project, of what was yesterday's temperature, became far more complex. The good outcome however is if we just chill and relax, all that is really needed from yesterday's weather is a rough guide. A few degrees here or there doesn't really matter. We just want to know what yesterday's weather is so we can compare it to today. Is it going to be similar, hotter, or cooler? The answer doesn't need high precision.
Kelvin Eldridge
www.WeatherYesterday.com.au
PS. Unlike some sites this post is not meant to be a criticism of the Bureau of Meteorology. Weather is not an exact science. The resources provided by the BOM are used by most of us most days of the year and are appreciated. I have no idea if the actual historical raw data is being modified and I certainly hope it isn't. Modelling isn't the raw data, just someone's interpretation of the raw data, and that can and will change over time as technology and knowledge changes.
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