You will work with data covering the period from 1955 to 2020. The data come from two sources:
-
From the National Oceanic and Atmospheric Administration's (NOAA) National Centers for Environmental Information (https://www.ncdc.noaa.gov/cdo-web/) and more specifically https://www.ncdc.noaa.gov/cdo-web/search.
-
Since we are interested in Athens, we will use data from the Hellenikon weather station and focus on the average daily temperature. The data for the period 1955 to 2020 can be found in the file
noaa_hellinikon_1995_2020.csv.zip(but you can take the opportunity to see what kind of data NOAA offers for free, it is an example to follow). -
Check the completeness of the data. What data are missing?
-
To fill in as much of the missing data as possible, you will use a second dataset available at https://data.hellenicdataservice.gr/dataset/66e1c19a-7b0e-456f-b465-b301a1130e3f. This dataset only covers the period from 2010-2019. You will get the data for Athens (
athens.csv, you will have to download it yourself). Attention to the documentation of the data.
The Hellenic Meteorological Service (EMY) has published a report dealing with extreme weather events for 2020. The report is available at http://www.hnms.gr/emy/en/pdata/2020_GRsignificantEVENT_en.pdata. On page 7 of the report there is a graph showing the deviation of the average daily summer daily temperature from the reference temperature derived from the years 1971-2000.
You will make your own version of the graph, using the mean daily summer temperature from 1974-1999 as the reference temperature. Your graph should be similar to the one shown below. The blue line on the graph is the 10 year rolling average. How do you interpret the graph?
You will find the average temperature of each day for each year in the period from 1955 to 2020. Then you will create a graph of the average temperature of each day for each year. The graph will have one line for each year, and will have been smoothed by taking a 30 day rolling average window. Each line will have a different color, from lightest to darkest, as the year increases, as you can see in the chart below.
On the graph you will add a line showing the average reference temperature of each day for the period 1974-1999 (it is the black line in the graph below). This line will also have been smoothed with a 30-day rolling window. How do you interpret the figure?