130 likes | 213 Views
Moisture convergence over the Amazon basin during two contrasting years 2005 and 2007. 1,2 Prakki Satyamurty, 2 Gilvan Sampaio de Oliveira, 1,3 Aline Anderson Castro, 1 Antonio Ocimar Manzi 1 INPA, Manaus 2 INPE, São José dos Campos 3 IAG/USP, São Paulo
E N D
Moisture convergence over the Amazon basin during two contrasting years 2005 and 2007 1,2 Prakki Satyamurty, 2Gilvan Sampaio de Oliveira, 1,3Aline Anderson Castro, 1Antonio Ocimar Manzi 1INPA, Manaus 2INPE, São José dos Campos 3IAG/USP, São Paulo Acknowledgements: FAPEAM and Josefina Moraes Arraut
Summary • Introduction; • Method; • Results; • Conclusion.
Introduction • Marengo (2004): interdecadal variability in rainfall in Amazônia; • Marengo (2007): drought in Amazônia in 2005; • What causes drought in this large river basin? • Changes in the planetary scale circulation and consequently changes in H2O transport; • Study these changes and it’s convergence in two contrasting years: 2005 and 2007.
P E Method • Moisture budget equation for the atmosphere: E = evap.; P = precip.; w = precipitable water • Time average or Our enphasis is on
Target area is considered Eq – 15ºS; 70ºW – 45ºW – Amazonia. • Seasons: • DJF: Austral summer; • MAM: Austral fall; • JJA: Austral winter; • SON: Austral spring.
H2O transport in the column 1000 hPa to 300 hPa Annual Data source: NCEP Reanalysis Units: 106 kg/s
H2O transport in the column 1000 hPa to 300 hPa DEC-JAN-FEB Data source: NCEP Reanalysis Units: 106 kg/s
H2O transport in the column 1000 hPa to 300 hPa MAR-APR-MAY Data source: NCEP Reanalysis Units: 106 kg/s
H2O transport in the column 1000 hPa to 300 hPa JUN-JUL-AUG Data source: NCEP Reanalysis Units: 106 kg/s
H2O transport in the column 1000 hPa to 300 hPa SEP-OCT-NOV Data source: NCEP Reanalysis Units: 106 kg/s
Net H2O convergence in Amazônia (SH) (106 kg/s) • 220x106 kg/s over the target area is equal to 5 mm/day
Conclusions • Target area did not suffer drought in 2005 due to reduction in H2O convergence; • Both 2005 and 2007 suffered reduction in annual, JJA and SON convergence; • In JJA northern border presented near zero H2O transport; • Transport at the northern border has a large seasonal cycle; • Sources of H2O for Amazon are the South and North Atlantic Oceans.