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Possible sources of long-term variations in the mid-latitude ionosphere
(Bentham open, 2011-10)
Trends in the upper atmosphere, together with the global warming of the lower atmosphere, are part of the global change of the Earth system. In the present work, which is focused in the upper atmosphere, long-term variations ...
Trends in total ozone and the effect of the equatorial zonal wind QBO
(Elsevier, 2010-05)
Trends in total column ozone have been analyzed in terms of the equatorial zonal wind. We used zonal monthly mean total ozone from Total Ozone Mapping Spectrometer (TOMS) and monthly mean zonal wind in the equatorial ...
Long-term changes in solar quiet (Sq) geomagnetic variations related to Earth?s magnetic field secular variation
(American Geophysical Union, 2013-01)
The daily amplitude of the solar quiet (Sq) magnetic variation of the horizontal intensity, H, of observatories at low and midlatitudes is analyzed, in search of significant long‐term trends. These trends are expected based ...
On the inclusion of data from solar cycle 19 to estimate F2 layer characteristic long term trend
(Editrice Compositori Bologna, 2015-04)
The effect of including solar cycle 19 (1954-1964) in ionospheric trend estimation is assessed using experimental foF2 values. The dominant influenceon the F2 layer is solar EUV radiation. In fact, around 90% of inter-annual ...
Earth's magnetic field effect on MUF calculation and consequences for hmF2 trend estimates
(Elsevier, 2017-10)
Knowledge of the state of the upper atmosphere, and in particular of the ionosphere, is essential in several applications such as systems used in radio frequency communications, satellite positioning and navigation. In ...
Evaluation of the ability of CMIP6 models to simulate precipitation over Southwestern South America: Climatic features and long-term trends (1901?2014)
(Elsevier Science Inc, 2020-09)
This study evaluates the performance of precipitation simulated in the historical runs of the Climate Model Intercomparison Project Phase 6 (CMPI6) in capturing the complex spatial and temporal patterns observed over ...
Trend-cycles of vegetation dynamics as a tool for land degradation assessment and monitoring
(Elsevier, 2019-07)
The use of time series of Normalized Difference Vegetation Index (NDVI), obtained from satellite sensors has become frequent in studies for land degradation assessment and monitoring. Linear trends of NDVI are usually ...
Long-term trend of the ionospheric F2 layer peak height at a southern low latitude station
(Pergamon-Elsevier Science Ltd, 2002-02)
The trend of the peak height of the ionospheric F2 layer, hmF2, during three solar cycles (1957?1986) at Tucuman (26.9°S, 65.4°W), station located at the southern peak of the equatorial anomaly, has been estimated. hmF2 ...
Breaks, Trends and the Attribution of Climate Change: A Time-Series Analysis
(Pontificia Universidad Católica del Perú, 2019)
Land cover and precipitation controls over long-term trends in carbon gains in the grassland biome of South America
(Ecological Society of America, 2015-10)
Carbon gains are a key aspect of ecosystem functioning since they represent the energy available for upper trophic levels. Carbon gains (or primary production) are strongly correlated with other ecosystem attributes such ...