Regime t?rmico da camada ativa e pemafrost na Pen?nsula de Keller, Ilha Rei George, Ant?rtica (2011-2014)

• Main Author: CHAVES, Daniela Augusto
• Other Authors: Silva, Leonardo Duarte Batista da
• Format: Others
• Language: Portuguese
• Published: Universidade Federal Rural do Rio de Janeiro 2018
• Subjects: Regime t?rmico do solo; Difusividade t?rmica; An?lise harm?nica; Soil thermal regime; Thermal diffusivity; Harmonic analysis; Recursos Naturais e Prote??o Ambiental
• Online Access: https://tede.ufrrj.br/jspui/handle/jspui/2385

Submitted by Jorge Silva ([e-mail]) on 2018-08-24T19:38:47Z No. of bitstreams: 1 2016 - Daniela Augusto Chaves.pdf: 7459629 bytes, checksum: db78e044349231645bd60b6c5fb4c66e (MD5) === Made available in DSpace on 2018-08-24T19:38:47Z (GMT). No. of bitstreams: 1 2016 - Daniela Augusto Chaves.pdf: 7459629 bytes, checksum: db78e044349231645bd60b6c5fb4c66e (MD5) Previous issue date: 2016-02-25 === CAPES === The monitoring of soil thermal regime in periglacial environment is critical to identify the presence of permafrost and the thickness of the active layer. This study was conducted to identify factors that influence the soil thermal regime in Keller Peninsula, from 02/2011 to 02/2015. For such monitoring were installed air temperature sensors (Tar) and soil (Ts) and soil moisture at different depths and sites in Keller Peninsula. Preliminary analyzes of the data were based on the monthly average, annual; maximum and minimum averages and seasonal averages of Tar; Ts and soil moisture at different depths in the monitoring sites Ipanema Ref?gio II, Punta and site soil with Standard. After these analyzes identified the days of freezing, thawing, isothermal and freezing / thawing for each depth; the frequency distribution of temperature and temperature fluctuation during the period studied. The analyzes were carried out: the cross-correlation between the AAO series (Antarctic Oscillation Index), SOI (Southern Oscillation Index), Tar and Ts; linar simple regression between the annual average temperatures and the highest average maximum and annual minimum; Multiple linear regression between moisture apparent soil thermal difuvividade (DTA); N_fator the rate of freezing and its relationship with DTA and; the harmonic analysis of the AAO series, SOI, MEI (multivariate ENSO index), Tar and Ts. The highest and lowest Tar annual average in the four years and four sites studied was 1.7 ?C on site Ref?gio II and 4.8 ?C in place with Standard Solo, respectively. The period in which the soil has more time under the active layer system was Ipanema and Ref?gio II. The highest and the lowest sum of degree days of thawing and freezing were 154.6 and 263.3, respectively Ref?gio II In cross-correlation analysis the delay phase between the waves of Tar and Ts was less than one month in all sites. The correlation between the AAO x Tar Tar and SOI x occurs up to 5 months delay between the phases. Simple linear regression analysis indicated that in Ipanema and Ref?gio II, the soil thermal regime restricted the active layer. On site soil with Standard and Punta Plaza thermal regime presented reached the permafrost before the layer of 0.80 and 1.00 m deep respectively. In the frequency histograms showed predominance of temperatures around 0 ?C and the first difference graph shown that temperature variations are stronger in summer. Multiple linear regrass?o analysis showed that the moisture influence on the DTA in most cases. The freezing N_fator was inversely proportional to close DTA the surface, but when compared with the DTA in depth the relationship approaches. The harmonic analysis identified that climate variability in ways that influenced the Tar these sites between the years 2011-2014, were the AAO and SOI indices. In general, the thermal insulation provided by covering the thickest snow in places Punta Plaza and Solo with Standard allowed the permafrost were found at depths less when compared to the Ref?gio II and Ipanema sites that were less thick blanket of snow. === O monitoramento do regime t?rmico do solo em ambiente periglacial ? fundamental para identificar a presen?a do permafrost e a espessura da camada ativa. Este estudo foi realizado para identificar os fatores que influenciam no regime t?rmico do solo na Pen?nsula Keller, entre 02/2011 a 02/2015. Para tal monitoramento foram instalados sensores de temperatura do ar (Tar) e do solo (Ts) e umidade do solo em diferentes profundidades e s?tios na Pen?nsula de Keller. As an?lises preliminares dos dados foram realizadas com base nas m?dias mensais, anuais; m?dias m?ximas e m?nimas e m?dias sazonais de Tar, Ts e umidade do solo em diferentes profundidades nos s?tios de monitoramento Ipanema, Ref?gio II, Punta e s?tio Solo com Padr?o. Ap?s essas an?lises foram identificados os dias de congelamento, descongelamento, isot?rmicos e congelamento/descongelamento para cada profundidade; as frequ?ncias de distribui??o das temperaturas e oscila??o de temperatura durante o per?odo estudado. As an?lises realizadas foram: a de correla??o cruzada entre as s?ries de AAO (Antarctic Oscillation Index), SOI (Southern Oscillation Index), Tar e Ts; a regress?o linar simples entre as temperaturas m?dias anuais e a maior m?dia m?xima e m?nima anuais; a regress?o linear m?ltipla entre umidade a difuvividade t?rmica aparente do solo (DTA); o ?ndice N_fator de congelamento e sua rela??o com a DTA e; a an?lise harm?nica das s?ries AAO, SOI, MEI (multivariate ENSO index), Tar e Ts. A maior e a menor Tar m?dia anual nos quatro anos e nos quatro s?tios estudados foi de -1,7 ?C no s?tio Ref?gio II e de ?4,8 ?C no s?tio Solo com Padr?o, respectivamente. O per?odo em que o solo apresentou mais tempo sob o regime de camada ativa foi Ipanema e Ref?gio II. A maior e a menor soma de graus dias de descongelamento e congelamento foram de 154,6 e ?263,3, respectivamente em Ref?gio II. Na an?lise de correla??o cruzada o atraso de fases entre as ondas de Tar e Ts foi inferior a um m?s em todos os s?tios. A correla??o entre a AAO x Tar e SOI x Tar ocorre com at? cinco meses de atraso entre as fases. A an?lise de regress?o linear simples indicou que, em Ipanema e em Ref?gio II, o regime t?rmico do solo se restringe a camada ativa. No s?tio Solo com Padr?o e Punta Plaza o regime t?rmico apresentado alcan?ou o permafrost antes da camada de 0,80 e 1,00 m de profundidade respectivamente. Os histogramas de frequ?ncia apresentaram predomin?ncia de temperaturas em torno de 0 ?C e o gr?fico de primeira diferen?a mostrou que as varia??es da temperatura foram mais fortes no ver?o. A an?lise de regrass?o linear m?ltipla mostrou que a umidade influencia na DTA na maior parte dos casos. O N_fator de congelamento foi inversamente proporcional a DTA pr?xima a superf?cie, por?m quando o compara com a DTA em profundidade essa rela??o se aproxima. A an?lise harm?nica permitiu identificar que os modos de variabilidade clim?tica que influenciaram a Tar nesses s?tios, entre os anos de 2011 a 2014, foram os ?ndices AAO e SOI. De maneira geral, o isolamento t?rmico proporcionado por cobertura da neve mais espessa nos s?tios Punta Plaza e Solo com Padr?o, permitiu que o permafrost fosse encontrado a profundidades menores quando comparado com os s?tios Ref?gio II e Ipanema, que obtiveram cobertura da neve menos espessa.