author = "Geirinhas, Jo{\~a}o L. and Trigo, Ricardo M. and Libonati, Renata 
                         and Coelho, Caio Augusto dos Santos and Palmeira, Ana Cristina",
          affiliation = "{Faculdade de Ci{\^e}ncias da Universidade de Lisboa} and 
                         {Faculdade de Ci{\^e}ncias da Universidade de Lisboa} and 
                         {Universidade Federal do Rio de Janeiro (UFRJ)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Universidade Federal 
                         do Rio de Janeiro (UFRJ)}",
                title = "Climatic and synoptic characterization of heat waves in Brazil",
              journal = "International Journal of Climatology",
                 year = "2018",
               volume = "38",
               number = "4",
                pages = "1760--1776",
                month = "Mar.",
             keywords = "heat waves, Brazil, atmospheric circulation patterns.",
             abstract = "According to the latest global and regional circulation models, 
                         the probability of occurrence of large heat waves (HWs), such as 
                         the 2003 European or the 2010 Russian events will increase 
                         significantly in the following decades under most climate 
                         scenarios. Currently, there are numerous studies for the Northern 
                         Hemisphere characterizing HWs and evaluating their impacts in 
                         several areas such as public health, economy, and agriculture. 
                         However, over South America, and in particular for Brazil, similar 
                         analysis is lacking despite its large geographical extension and 
                         numerous population potentially affected. Here we perform an 
                         assessment of HW events and characteristics recorded in six large 
                         Brazilian cities during the last five decades. The performed 
                         analysis reveals the existence of positive and significant trends 
                         in HW frequency since the 1980s, particularly for the cities of 
                         SAo Paulo, Manaus, and Recife. Over the last decades, Brasilia was 
                         the city that recorded the highest number of days per year under a 
                         HW regime, contrasting with Rio de Janeiro that recorded the 
                         lowest value. The assessment of the large-scale atmospheric 
                         circulation patterns associated with summer HWs, indicated for 
                         Porto Alegre, SAo Paulo, Rio de Janeiro, and Brasilia the presence 
                         of well-marked concentric and positive 500 hPa geopotential height 
                         anomalies followed by positive 850 hPa temperature anomalies. 
                         These anomalies are likely associated with quasi-stationary 
                         anticyclonic systems promoted by anomalous westward displacements 
                         of the South Atlantic Subtropical High System which are related to 
                         a weakening of other transients (and non-transient) systems such 
                         the Intertropical Convergence Zone (ITCZ) and the South Atlantic 
                         Convergence Zone. For Manaus, the identified anomalies are linked 
                         to a northward displacement of the ITCZ. This configuration is 
                         compatible with an increase in solar radiative pattern and 
                         decreased soil moisture, enhancing surface temperature values, 
                         possibly associated with positive feedback mechanisms between soil 
                         and the atmosphere.",
                  doi = "10.1002/joc.5294",
                  url = "http://dx.doi.org/10.1002/joc.5294",
                 issn = "0899-8418",
             language = "en",
           targetfile = "geirinhas-climatic.pdf",
        urlaccessdate = "11 maio 2021"