While we do not have day-to-day weather data from before about 1850, weather data can be teased out of contemporaneous reports.
For example, because of documentation in the Iberian Peninsula (called "Al-Andalus") under Islamic rulers, we know that the peninsula experienced periods of drought, some long and some short.
"By collecting these events, we can say that there were important droughts in Al-Andalus between the 748-754, 812-823 and 867-879 periods in which we have come across plenty of references to droughts and related famines, which even led to people emigrating to North Africa," states Domínguez.Additionally, weather data collected in 1724 indicate that a large tropical storm (a precursor to hurricanes) swept over the Peninsula.
Over 100,000 observations from that period taken in 16 towns such as Cadiz, Madrid, Badajoz, Palma de Mallorca, Valencia, Zaragoza, Bilbao, Palencia or La Coruña have been digitalised. This has shown the existence of high rainfall anomalies, such as that of 1780 or the cold period felt throughout Europe the year after the great eruption of the Mount Tambora volcano (Indonesia) in 1815.One of the major problems with the "global warming is causing climate change" meme are the over-hyped predictions for "extreme weather." Extreme weather, such as droughts in the Iberian Peninsula or California, are normal, but irregular, features of the world's climate.