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EARLY METEOROLOGICAL DATA IN SOUTHERN SPAIN, 1780-1830 F. S. Rodrigo Department of Applied Physics , University of Almería La Cañada de San Urbano, s/n, 04120, Almería ( Spain ) frodrigo@ual.es. 3. Rainy days in Seville , 1778-1785 ( source N). Flood , 21/12/1783. 1783. 1784. 1785.
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EARLY METEOROLOGICAL DATA IN SOUTHERN SPAIN, 1780-1830 F. S. Rodrigo Department of AppliedPhysics, University of Almería La Cañada de San Urbano, s/n, 04120, Almería (Spain) frodrigo@ual.es 3. Rainydays in Seville, 1778-1785 (source N). Flood, 21/12/1783 1783 1784 1785 Intense and continuousrainfalls March 1785 Introduction Thegrowingevidence of ananthropogenicallyinducedclimaticchange and theneedto compare present dayclimatewiththat of pastcenturies, has boostedthesearch of earlymeteorological data fromallkind of historical archives. Theobjective of thisworkistopresent new data fromAndalusia (southernSpain) correspondingtothe period 1780-1830, previoustotheestablishment of anofficialmeteorologicalservice in Spain. This period coincides withthe so-called ‘Dalton Minimum’, a period of minimum solar activity and intense volcaniceruptions. Data sources are earlynewspapers and medicalstudiesinterested in theinfluence of environment conditionsonhealth and illness. Someexamples are analyzed and theirutility as data sourcesisstudied. Lakagígar, Iceland 4. Temperatures in Granada, June1796-May1797, January-February 1813, and July 1820 (sources M, EP, EC). Comparisonwithmonthly mean of dailymaximumtemperaturesduring 1961-1990. 1796 1797 5. Middaytemperatures in Cádiz/San Fernando, 1789-1832 (sources W, A, D, P, R). Examples (December, March) of monthlymeans of midday T (data expressed in ºC as anomalies of themonthly mean of dailymaximumtemperaturesduring 1961-1990). Lack of informationonmetadata (instruments, exposureconditions, etc) Sourcesprovidevery short series. Fragmentary and disperse information. Discrepanciesbetweencontemporary series. 2. Data sources NR=number of rainydays; T = temperature (ºR, ºF, fraction of degree); p = pressure (English/French inches, lines, fractions of line); Wd = winddirection (16-point compass); A = qualitativedescription of atmosphericevents (rainfall, fog, cloudiness, storms, etc.). Random error in the original documents and mistakesduringthedigitazingwerechecked and corrected. Independentdocumentary data sources (‘Salvá-Sinobas’ projectdatabase) wereusedto look forcontemporary extreme events (indicatedby in thegraphs). (Wheeler, D., 1995. Early instrumental weather data from Cádiz: a study of late eighteenth and earlynineteenthcentury records, Int. J. Climatol., 15: 801-810). Itisdifficulttoconstructhomogeneized time series = Volcaniceruptions: Lakagígar, Iceland, June 1783 Etna, Italy, July 1787 St Helens, USA, January 1800 Tambora, Indonesia, April 1815 Galunggung, Indonesia, October 1822 Cold wave, 1799 Snowfalls, 1803 6. Conclusions. Annualcycles are reasonablywellreproduced. Temperature data in theexamplesstudiedwereslightlylowerthanthemodernreferencevalues. Data sources, in spite of theirspatio-temporal dispersion, mayofferinterestinginformationon extreme eventsrecorded in otherindependentdocumentary data sources. A general preliminar viewmaybeobtained, withconditionswetter and colderthanduringthereferenceperiod 1961-1990. Frequent and intense volcaniceruptionsalongwiththeminimum solar activitymaybethemainforcingfactors. Acknowledgments ThisworkwasfinancedbytheSpanishScienceMinistry (project CGL2007-65546-C03-01/CLI) and theEnvironmentMinistry (project ‘Salvá-Sinobas’, referencenumber 200800050083542).