[1] A workshop on climate change indices was held at the Mauritius Meteorological Services in October 2009 to produce the first analysis of climate trends for the countries of the western Indian Ocean. Scientists brought their long-term daily temperature and precipitation for a careful assessment of data quality and homogeneity, and for the preparation of climate change indices. This paper reports on the trends in daily and extreme temperature and precipitation indices for 1961-2008. The results indicate a definitive warming of surface air temperature at land stations. Annual means of the daytime and nighttime temperatures have increased at a similar rate, leading to no discernible change in the diurnal temperature range. Significant increasing trends were found in the frequency of warm days and warm nights, while decreasing trends were observed in the frequency of cold days and cold nights. Moreover, it seems that the warm extremes have changed more than the cold extremes in the western Indian Ocean region. Trends in precipitation indices are generally weak and show less spatial coherence. Regionally, a significant decrease was found in the annual total rainfall for the past 48 years. The results also show some increase in consecutive dry days, no change in daily intensity and consecutive wet days, and a decrease in extreme precipitation events. Temperature indices are highly correlated with sea surface temperatures of the region, whereas weak correlations are found with the precipitation indices.Citation: Vincent, L. A., et al. (2011), Observed trends in indices of daily and extreme temperature and precipitation for the

The spatial and temporal distribution of tropospheric water vapour in the South Indian Ocean (SIO) basin is investigated using observations collected from twelve GNSS stations spanning the basin. The comparison of GNSS‐derived integrated water vapour (IWV) content against radiosoundings and satellite‐borne microwave radiometer data shows good agreement, with global uncertainties ranging from 0.76 to 1.17 kg·m−2, depending on GNSS station locations. GNSS‐derived IWV contents show a strong seasonal cycle, characterized by higher water vapour content during the austral summer, when the InterTropical Convergence Zone (ITCZ) is located in the Southern Hemisphere. At the seasonal time‐scale, the observed annual IWV amplitude varies from 10 to 15 kg·m−2 near the Equator to 20 to 30 kg·m−2 in the Subtropics. The GNSS IWV signature of the Madden–Julian Oscillation (MJO) is hardly noticeable during the Austral winter, but varies from 1–2 to 4 kg·m−2 between the active and suppressed phases of the MJO during austral summer. At diurnal time‐scales, GNSS IWV shows larger diurnal amplitude over land (2–3 kg·m−2) than over open ocean (1–2 kg·m−2), with highest amplitudes (up to 7 kg·m−2) observed over large and mountainous islands. The phase analysis of the IWV diurnal cycle indicates that the diurnal maximum (minimum) is reached in the late afternoon/evening (morning) over land, at night (mid‐day) over ocean and in the early morning (late afternoon) at coastal locations. A comparison of GNSS‐derived IWV contents against fifth‐generation European Centre for Medium‐range Weather Forecasts (ECMWF) Reanalysis (ERA5) data shows that ERA5 generally correctly reproduces the IWV content at both seasonal, intra‐seasonal and diurnal time‐scales, although some discrepancies can be noticed over small islands characterised by steep orography. The signature of the MJO in ERA5 also shows good agreement with GNSS observations at most studied locations.

No abstract

No abstract

The Saguenay region is divided into three lithostructural units, namely (1) a gneiss complex; (2) batholithic anorthosite and mangerite complexes; and (3) late- to post-kinematic plutons. Three age groups of rocks in the gneiss complex are defined by increasing complexity of structure and mobilizates. Rocks of age group I (paragneiss, granite I) show extremely complex structure and contain three generations of mobilizates. Structures in rocks of age group II (granite II, amphibolite II dykes) are less complex and two generations of mobilizates are present. Rocks of age group III (granite III, amphibolite III dykes) contain one foliation and one generation of mobilizates. Metamorphosed mafic dykes are stratigraphic markers permitting correlation of age groups over vast tracts of terrain.Well-preserved igneous structures (cumulate layering) and textures (cumulate textures, ophitic textures) prove that anorthosite and mangerite crystallized from magmas. Anorthosite has been granulated and foliated, metamorphosed at high pressure with formation of orthopyroxene–spinel coronas by reaction of olivine and plagioclase, and intruded by three successive generations of mafic dykes (diorite, leucotroctolite, amphibolite IIIa).Mineral associations in the gneiss complex suggest metamorphism during slow cooling at about 5 kbar (500 MPa) pressure. Successive mineral associations in anorthosite and its cross-cutting dykes suggest a history of decreasing pressure (from >7–9 kbar (700–900 MPa)) and temperature (from 1200–1400 °C). Thus the anorthosite was emplaced at its present level by diapirism. Structures in the gneiss complex and anorthosite are consistent with the model of diapiric rise of anorthosite and mangerite plutons, but suggest presence of a generation of orogenic structures prior to diapirism.