The real climate change

Weather change is not climate change

“Climate change” is mentioned often today in a context that means “weather change”. There is a difference between weather and climate. Climate is the long-term weather pattern. Weather influences what clothes you wear on a given day, while the climate influences the contents of your entire wardrobe.

The most common definition is that climate is the weather averaged over 30 years or the statistical properties of the weather when they are determined over a period of at least 30 years. This is the convention used by the World Meteorological Organization (WMO). And in Australia, the current reference climate normal is generated over the 30-year period 1 January 1961 to 31 December 1990. But this is different to most data on global warming which is presented as annual averages.

Government agencies

The National Oceanic and Atmospheric Administration (NOAA) has a web page that claims to generate “Climate at a glance” by graphing a time series of surface temperature anomalies. This shows the trend of surface temperatures from 1880 to 2021. But the timescales that they allow for averaging the temperatures varies from 1 month to 5-years! It doesn’t go up to 30 years! This is weather, not climate! So the page is titled wrongly.

The National Aeronautics and Space Administration (NASA) explains the difference between climate change and global warming as follows.

“Global warming” refers to the long-term warming of the planet. Global temperature shows a well-documented rise since the early 20th century and most notably since the late 1970s. Worldwide, since 1880 the average surface temperature has risen about 1 °C.

“Climate change” encompasses global warming, but refers to the broader range of changes that are happening to our planet. These include rising sea levels; shrinking mountain glaciers; accelerating ice melt in Greenland, Antarctica and the Arctic; and shifts in flower/plant blooming times. These are all consequences of the warming, which is caused mainly by people burning fossil fuels and putting out heat-trapping gases into the air. The terms “global warming” and “climate change” are sometimes used interchangeably, but strictly they refer to slightly different things.

Once again, there is no mention of 30-year mean statistics! And they say that the terms “global warming” and “climate change” are “sometimes used” interchangeably. I think it would be more accurate to say that they are “often” used interchangeably! How unprofessional to use shoddy terminology! I learnt about the difference between weather and climate in Climatology at Macquarie University many years ago.

And the Australian Bureau of Meteorology’s “Annual climate statement 2020” contains no climatic data! The longest averages used are for 11 years, which is significantly lower than 30 years. Because weather is more variable than climate, it’s easier to break records with weather data than it is with climate data. Based on its content, it should be titled the “Annual weather statement 2020”, but that wouldn’t suit the current paradigm!

Missing temperature data

The main evidence of climate change is said to be the trend in global temperatures. So I searched on the internet for a graph of the global trend in 30-year mean surface temperatures. Guess what? No-one has posted it!

So I searched on the internet for the numerical data on the global trend in 30-year mean surface temperatures. Guess what? No-one has posted it!

So I had to use some 10-year (decade) mean surface temperature data that I found from NASA to determine the 30-year (tricade) mean data using a spreadsheet (see graph below).

The real climate change graph for temperature

All the statistics available today on global warming and climate change show weather changes, and not climate changes.

The graph of the real climate change in global temperatures (from NASA GISS data) is shown here. This is a unique graph; I can’t see it anywhere else on the internet! It shows an increase in the 30-year mean temperature of 0.76 ⁰C between 1900-1929 and 1990-2019. This is equivalent to an increase of 0.25 ⁰C each 30 years. The accuracy of this estimate would depend on the accuracy of historical surface temperature data and the accuracy of the method of interpolation/extrapolation of temperatures across the surface of the earth from sparse measurement locations. In particular, the uncertainty in the determination of global mean temperatures in the early 20th century would add to the uncertainty in these estimates of the temperature trend. The raw temperature data have also been homogenized, in a process which may have artificially enhanced global warming.

The trend in human emissions of carbon dioxide, increases at a slow rate from 1890 to1950 and at a greater rate since 1950. But this pattern is not evident in the graph of the real climate change in global temperatures where the trend from 1990-1929 to 1930-1959 (over 30 years) is similar to the trend from 1930-1959 to 1990-2019 (over 60 years). There is no overall change in the trend in the temperature data. This shows that natural variability in atmospheric temperatures dominates the impact of changes in the human emissions of carbon dioxide.

By the way, temperature measurements of the lower troposphere by satellite have only been made for 40 years, which is not long enough to determine climatic trends.

Other climatic variables

What about other climatic variables like sea levels and the extent of glaciers and ice on the earth’s surface?

Sea level is primarily measured using tide stations and satellite laser altimeters. Tide gauges can only measure relative sea level, whilst satellites can also measure absolute sea level changes. Tide gauges tell us what is happening at a local level—the height of the water as measured along the coast relative to a specific point on land. Satellite measurements provide us with the average height of the entire ocean. Sea level rise at specific locations may be more or less than the global average due to local factors such as land subsidence from natural processes and withdrawal of groundwater and fossil fuels, changes in regional ocean currents, and whether the land is still rebounding from the weight of ice age glaciers about 4,000 years ago (according to the Bible).

Missing sea level data

Changes in sea level is said to be one of the consequences of global warming. So I searched on the internet for a graph of the global trend in 30-year mean sea levels. Guess what? No-one has posted it!

So I searched on the internet for the numerical data on the global trend in 30-year mean sea levels. Guess what? No-one has posted it!

So I had to use some seasonal sea level data I found on a NOAA webpage to determine the 30-year (tricade) mean data using a spreadsheet (see graph below).

The real climate change graph for sea level

The graph of the real climate change in sea level (from NOAA’s climate dashboard) is shown here. This is a unique graph; I can’t see it anywhere else on the internet! It shows an increase in the 30-year mean sea level of 155 mm between 1900-1929 and 1990-2019. This is equivalent to an increase of 50 mm each 30 years. The accuracy of this estimate would depend on the accuracy of historical sea level data and the accuracy of the method of interpolation/extrapolation of sea levels across the oceans from sparse measurement locations. In particular, the uncertainty in the determination of global mean sea levels in the early 20^th century would add to the uncertainty in these estimates of the sea level trend.

By the way, sea level measurements by satellite have only been made for 29 years, which is not long enough to determine climatic trends.

Discussion

What is causing the minor (0.76 ⁰C) climate temperature change over this period? Climate alarmists believe that it is primarily due to human emissions of greenhouse gases. But if the greenhouse effect has a significant influence on this temperature trend and if the greenhouse gases are virtually saturated, then the trend will level off and not go out of control.

Government agencies and the Intergovernmental Panel on Climate Change (IPCC) are being deceitful when they use the term “Climate change” for statistics which have not been averaged (or processed) over 30-year periods. For example, when meteorological agencies say that a year is the warmest ever, they are addressing weather and not climate.

So the word “climate” is now being used for circumstances that are outside the traditional meaning. Weather and climate are confused. Is this an example of a change in meaning of a word or a mixed adjective or is it Newspeak (1984)?

Global temperatures are often compared to those in the pre-industrial era of the 19^th century. But this is near the little ice age (AD 1400 – 1850), so it shouldn’t be considered to be the normal or natural temperature. Instead, it would have been below the normal or natural temperature. This means that some (or much) of the increase in temperatures in the 20^th century would have been due to the recovery of the atmosphere from the little ice age. So the temperatures today are probably nearer to normal than most people think.

Conclusion

All the statistics available today on global warming and climate change show weather changes, and not climate changes. So the word “climate” is being used to describe “weather”. This incorrect and confusing word usage exaggerates global warming.

A graph of the real climate change in global temperatures has been produced for the past 120 years. It shows an increase in the 30-year mean temperature of 0.76 ⁰C.

And a graph of the real climate change in global sea levels has been produced for the past 120 years. It shows an increase in the 30-year mean sea level of 155 mm.

Appendix: Message sent to Australian Bureau of Meteorology (BOM) in March 2021

“Australia’s climate statement 2020” is an oxymoron. It should be titled, “Australia’s weather statement 2020” because it only contains weather data and no climate data. For example, if it was a climate statement, I would expect it to compare 1961-1990 data with 1991-2020 data. Please explain why annual data is now called “climatic” data and not “weather” data. Or have the BOM & WMO etc changed the definition of the word “climate”?

As of 15 April, there has been no response from the BOM.

Poscript: Australia’s climate statement 2021

“Australia’s climate statement 2021” compares 2021 data with 1961-1990 data. This is comparing “weather” with “climate! How confusing!

Written, February 2021

Also see: Is there a climate crisis?