Photo by Patrick Hendry on Unsplash

The Global Surface Temperature Data

The global surface temperature data are visualized in this article. The global surface temperature rises very steeply and consistently since 1980s decade compared to all previous periods. This trend is alarming and should be addressed more seriously by us, the people and countries of the world.

The data visualized in this article are from GISTEMP. The data contain the surface temperatures of land and sea from the period of year 1880 up to 2021. The core variables of the data are temperature anomalies (deviations). These deviations are the differences between the temperature from a certain measurement time and the average measurement from the base period of the years 1951 to 1980. The measurement month and year, and the measurement station’s geographic zone were also recorded. These data can be useful to monitor the state of global warming and climate change.

The global surface temperature data dashboard is available here.

Visualizations
(see analysis of patterns)

Analysis of Patterns
(analysis written on 12/06/2021)

Measurements of temperature deviations by year and month show steep and consistent rise since the 1980s up to 2021. Before 1980s, the average deviation is -0,14. Meanwhile, the average deviation from 1980 to 2021 is 0,52. Before 1980s the pattern shows an unusual ‘hill’ in the 1940s followed by an elevated but rather flat level in the 1950s to 1970s.

So far, the slowing of human activities in COVID-19 pandemic of 2020 and 2021 doesn’t seem to have any immediate effect to slow the temperature rise.

Deviation fluctuation trends of southern and northern hemispheres move closely with each other until early 2000s. From 2000s the northern hemisphere trend starts to create large gaps as it rises above the trend of the southern hemisphere. In 1930s to 1960s the deviations of northern hemisphere also create marked gaps although not as large and persistent as the gaps in 2000s.

From the temperature deviations by month graph, it seems that fluctiations of one single month are generally consistent with other months of the same year throughout all years of the measurement period. The exceptions to this are December, January, and November in certain years.

The season pattern generally follows main pattern of deviation of hemispheres, although there are smaller gaps especially around 1930s to 1950s. There is a reversal of trends in 1920s. Before 1920s, the season deviations in the southern hemisphere are lower than those of the northern hemisphere. After 1920s, the season deviations of the northern hemisphere are generally higher than those of the southern hemisphere. This pattern is most clearly seen in winter and spring trends.

Deviation fluctuations of one single season in both hemispheres are almost wholly consistent with other seasons of the same year throughout the measurement period. One notable exception is the winters of the 1880s which have lower than deviations of other seasons of the same years.

Generally, the trends of the deviations according to their geographic zones follow a main pattern. However, notable exceptions exist. Zones 90S-64S and 64N-90N vastly differ from the main pattern in diverging ways, especially from 1920s to 1940s and from 1880s to 1900s. In 2000s, the 64N-90N trend consistently diverge vastly above the main pattern while 64S-44S fall relatively flat at slightly below the main pattern. Strangely, in 1900s the 64N-90N pattern switch places with 90S-64S. Before 1900s, the 64N-90N are below the main trend while the 90S-64S are above it. In 1900s the 90S-64S starts to drop below the main trend while the 64N-90N rises above the main trend. This reversal between 90S-64S and 64N-90N zones trends may be correlated with similar reversal found in the 1920s in the season chart.

Many specific patterns in the data deserve further investigations. My main takeaway here is the great concern for the consistent steep rise of temperature beginning in the 1970s up to the present day. That rise looks set to have serious effect on our global environment. To reverse or stop or even slow that trend seem to require many decades of efforts. This demands more coordinated, immediate, and strict actions from the people and countries of the world.

References

GISTEMP Team, 2021: GISS Surface Temperature Analysis (GISTEMP), version 4. NASA Goddard Institute for Space Studies. Dataset accessed 2021-06-06 at https://data.giss.nasa.gov/gistemp/.

Lenssen, N., G. Schmidt, J. Hansen, M. Menne, A. Persin, R. Ruedy, and D. Zyss, 2019: Improvements in the GISTEMP uncertainty model. J. Geophys. Res. Atmos., 124, no. 12, 6307-6326, doi:10.1029/2018JD029522.

(Featured Photo by Patrick Hendry on Unsplash)