Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-15T14:36:00Z No. of bitstreams: 1 MarcosAurelioFerreiraDosSantos_TESE.pdf: 1437668 bytes, checksum: 721d961caf43f4a527f834ddbdc21ac3 (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2016-01-25T12:39:36Z (GMT) No. of bitstreams: 1 MarcosAurelioFerreiraDosSantos_TESE.pdf: 1437668 bytes, checksum: 721d961caf43f4a527f834ddbdc21ac3 (MD5) / Made available in DSpace on 2016-01-25T12:39:36Z (GMT). No. of bitstreams: 1 MarcosAurelioFerreiraDosSantos_TESE.pdf: 1437668 bytes, checksum: 721d961caf43f4a527f834ddbdc21ac3 (MD5) Previous issue date: 2014-02-25 / O fluxo de calor e a difusividade t?rmica do solo s?o importantes componentes do balan?o de energia de superf?cie, particularmente para regi?es ?ridas e semi?ridas. O objetivo deste trabalho foi realizar a estimativa do fluxo de calor no solo, a partir da temperatura do solo medida em uma ?nica profundidade, baseado no m?todo da derivada fracion?ria de meia ordem proposta por Wang e Bras (1999), e estabelecer um m?todo capaz de estimar a difusividade t?rmica do solo baseado na derivada temporal fracion?ria de meiaordem da temperatura do solo. Os resultados de fluxo de calor no solo foram comparados com o fluxo de calor no solo medido atrav?s de 2 placas de fluxo, e a difusividade t?rmica estimada foi comparada com medidas realizadas ?in loco?. Os resultados obtidos mostram excelente concord?ncia entre o fluxo estimado a partir da solu??o adotada e o fluxo medido, permitindo estimativas de longo termo para o fluxo de calor no solo a partir da s?rie temporal de temperatura medida em uma ?nica profundidade, bem como os valores da difusividade t?rmica estimados pelo m?todo estabelecido se mostraram coerentes e concordantes com valores medidos ?in loco?, e com valores encontrados na literatura utilizando m?todos convencionais. / The soil heat flux and soil thermal diffusivity are important components of the surface energy balance, especially in ar id and semi-arid regions. The obj ective of this work was to carry out to estimate the soil heat flux from th e soil temperature measured at a single depth, based on the half-order time derivative met hod proposed by Wang and Bras (1999), and to establish a method capable of es timating the thermal diffusivity of the soil, based on the half order derivative, from the temporal series of soil temperature at two depths. The results obtained in the estimates of soil heat flux were compared with the values of soil heat flux measured through flux plates, and the thermal di ffusivity estimated was compared with the measurements carried out in situ. The results obtained showed excellent concordance between the estimated and measured soil heat flux, with correlation (r), coeffici ent of determination (R 2 ) and standard error (W/m 2 ) of: r = 0.99093, R 2 = 0.98194 and error = 2.56 (W/m 2 ) for estimated period of 10 days; r = 0,99069, R 2 = 0,98147 and error = 2.59 (W/m 2 ) for estimated period of 30 days; and r = 0,98974, R 2 = 0,97958 and error = 2.77 (W/m 2 ) for estimated period of 120 days. The values of thermal di ffusivity estimated by the proposed method showed to be coherent and consis tent with in situ measured va lues, and with the values found in the literature usi ng conventional methods.