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The development of cloud computing services is speeding up the rate in which the organizations ou... more The development of cloud computing services is speeding up the rate in which the organizations outsource their computational services or sell their idle computational resources. Even though migrating to the cloud remains a tempting trend from a financial perspective, there are several other aspects that must be taken into account by companies before they decide to do so. One of the most important aspect refers to security: while some cloud computing security issues are inherited from the solutions adopted to create such services, many new security questions that are particular to these solutions also arise, including those related to how the services are organized and which kind of service/data can be placed in the cloud. Aiming to give a better understanding of this complex scenario, in this article we identify and classify the main security concerns and solutions in cloud computing, and propose a taxonomy of security in cloud computing, giving an overview of the current status of security in this emerging technology.

Journal of Geophysical Research, 2000

The space-time variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in th... more The space-time variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in the vicinity of the island of Cuba, is examined using digital images obtained with the Coastal Zone Color Scanner sensor flown aboard the Nimbus 7 satellite from 1978 to 1986. The results are compared to historical in situ hydrographic observations. A marked seasonality in pigment concentration was observed in waters around Cuba, with an average of 0.07 mg m-3 in summer (April-September) and 0.13 mg m-3 during winter (October-March). The range of variation in pigment concentration was larger in the Gulf of Mexico relative to the western Caribbean Sea. We identified four biogeographical areas on the basis of groups of pixels with similar patterns of time variability. These are area I: southwest of Cuba, Yucatan Channel, and Florida Strait; area II: central Gulf of Mexico; area III: east of Cuba; and area IV: central Caribbean Sea, south of Jamaica and Hispaniola. Two major meteorological events led to anomalies in the seasonal cycle of pigment concentrations. During El Niño-Southern Oscillation (ENSO) of 1982-1983, positive anomalies were observed in the pigment concentration in the western IAS during winter months. This was associated with intense mixing of the water column by higher-frequency and stronger winds associated with cold fronts. ENSO 1982-1983 therefore had a fertilizing effect on the IAS region. Another positive anomaly was observed in 1980-1981, a non-ENSO period that featured higher hurricane and extratropical low-pressure activity.

Journal of Geophysical Research, 2000

The space-time variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in th... more The space-time variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in the vicinity of the island of Cuba, is examined using digital images obtained with the Coastal Zone Color Scanner sensor flown aboard the Nimbus 7 satellite from 1978 to 1986. The results are compared to historical in situ hydrographic observations. A marked seasonality in pigment concentration was observed in waters around Cuba, with an average of 0.07 mg m Ϫ3 in summer (April-September) and 0.13 mg m Ϫ3 during winter (October-March). The range of variation in pigment concentration was larger in the Gulf of Mexico relative to the western Caribbean Sea. We identified four biogeographical areas on the basis of groups of pixels with similar patterns of time variability. These are area I: southwest of Cuba, Yucatan Channel, and Florida Strait; area II: central Gulf of Mexico; area III: east of Cuba; and area IV: central Caribbean Sea, south of Jamaica and Hispaniola. Two major meteorological events led to anomalies in the seasonal cycle of pigment concentrations. During El Niño-Southern Oscillation (ENSO) of 1982-1983, positive anomalies were observed in the pigment concentration in the western IAS during winter months. This was associated with intense mixing of the water column by higher-frequency and stronger winds associated with cold fronts. ENSO 1982-1983 therefore had a fertilizing effect on the IAS region. Another positive anomaly was observed in 1980 -1981, a non-ENSO period that featured higher hurricane and extratropical low-pressure activity.

Journal of Geophysical Research, 2000

The space-time variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in th... more The space-time variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in the vicinity of the island of Cuba, is examined using digital images obtained with the Coastal Zone Color Scanner sensor flown aboard the Nimbus 7 satellite from 1978 to 1986. The results are compared to historical in situ hydrographic observations. A marked seasonality in pigment concentration was observed in waters around Cuba, with an average of 0.07 mg m Ϫ3 in summer (April-September) and 0.13 mg m Ϫ3 during winter (October-March). The range of variation in pigment concentration was larger in the Gulf of Mexico relative to the western Caribbean Sea. We identified four biogeographical areas on the basis of groups of pixels with similar patterns of time variability. These are area I: southwest of Cuba, Yucatan Channel, and Florida Strait; area II: central Gulf of Mexico; area III: east of Cuba; and area IV: central Caribbean Sea, south of Jamaica and Hispaniola. Two major meteorological events led to anomalies in the seasonal cycle of pigment concentrations. During El Niño-Southern Oscillation (ENSO) of 1982-1983, positive anomalies were observed in the pigment concentration in the western IAS during winter months. This was associated with intense mixing of the water column by higher-frequency and stronger winds associated with cold fronts. ENSO 1982-1983 therefore had a fertilizing effect on the IAS region. Another positive anomaly was observed in 1980 -1981, a non-ENSO period that featured higher hurricane and extratropical low-pressure activity.

Journal of Geophysical Research, 2000

The space-time variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in th... more The space-time variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in the vicinity of the island of Cuba, is examined using digital images obtained with the Coastal Zone Color Scanner sensor flown aboard the Nimbus 7 satellite from 1978 to 1986. The results are compared to historical in situ hydrographic observations. A marked seasonality in pigment concentration was observed in waters around Cuba, with an average of 0.07 mg m Ϫ3 in summer (April-September) and 0.13 mg m Ϫ3 during winter (October-March). The range of variation in pigment concentration was larger in the Gulf of Mexico relative to the western Caribbean Sea. We identified four biogeographical areas on the basis of groups of pixels with similar patterns of time variability. These are area I: southwest of Cuba, Yucatan Channel, and Florida Strait; area II: central Gulf of Mexico; area III: east of Cuba; and area IV: central Caribbean Sea, south of Jamaica and Hispaniola. Two major meteorological events led to anomalies in the seasonal cycle of pigment concentrations. During El Niño-Southern Oscillation (ENSO) of 1982-1983, positive anomalies were observed in the pigment concentration in the western IAS during winter months. This was associated with intense mixing of the water column by higher-frequency and stronger winds associated with cold fronts. ENSO 1982-1983 therefore had a fertilizing effect on the IAS region. Another positive anomaly was observed in 1980 -1981, a non-ENSO period that featured higher hurricane and extratropical low-pressure activity.

Journal of Geophysical Research, 2000

The space-time variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in th... more The space-time variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in the vicinity of the island of Cuba, is examined using digital images obtained with the Coastal Zone Color Scanner sensor flown aboard the Nimbus 7 satellite from 1978 to 1986. The results are compared to historical in situ hydrographic observations. A marked seasonality in pigment concentration was observed in waters around Cuba, with an average of 0.07 mg m Ϫ3 in summer (April-September) and 0.13 mg m Ϫ3 during winter (October-March). The range of variation in pigment concentration was larger in the Gulf of Mexico relative to the western Caribbean Sea. We identified four biogeographical areas on the basis of groups of pixels with similar patterns of time variability. These are area I: southwest of Cuba, Yucatan Channel, and Florida Strait; area II: central Gulf of Mexico; area III: east of Cuba; and area IV: central Caribbean Sea, south of Jamaica and Hispaniola. Two major meteorological events led to anomalies in the seasonal cycle of pigment concentrations. During El Niño-Southern Oscillation (ENSO) of 1982-1983, positive anomalies were observed in the pigment concentration in the western IAS during winter months. This was associated with intense mixing of the water column by higher-frequency and stronger winds associated with cold fronts. ENSO 1982-1983 therefore had a fertilizing effect on the IAS region. Another positive anomaly was observed in 1980 -1981, a non-ENSO period that featured higher hurricane and extratropical low-pressure activity.