Messinian salinity crisisThe Messinian salinity crisis (also referred to as the Messinian event, and in its latest stage as the Lago Mare event) was a geological event during which the Mediterranean Sea went into a cycle of partial or nearly complete desiccation (drying-up) throughout the latter part of the Messinian age of the Miocene epoch, from 5.96 to 5.33 Ma (million years ago). It ended with the Zanclean flood, when the Atlantic reclaimed the basin.
Canton of GenevaThe Canton of Geneva, officially the Republic and Canton of Geneva, is one of the 26 cantons forming the Swiss Confederation. It is composed of forty-five municipalities, and the seat of the government and parliament is in the City of Geneva. Geneva is the French-speaking westernmost canton of Switzerland. It lies at the western end of Lake Geneva and on both sides of the Rhone, its main river. Within the country, the canton shares borders with Vaud to the east, the only adjacent canton.
Severe weatherSevere weather is any dangerous meteorological phenomenon with the potential to cause damage, serious social disruption, or loss of human life. Types of severe weather phenomena vary, depending on the latitude, altitude, topography, and atmospheric conditions. High winds, hail, excessive precipitation, and wildfires are forms and effects of severe weather, as are thunderstorms, downbursts, tornadoes, waterspouts, tropical cyclones, and extratropical cyclones.
Clastic rockClastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus, chunks, and smaller grains of rock broken off other rocks by physical weathering. Geologists use the term clastic to refer to sedimentary rocks and particles in sediment transport, whether in suspension or as bed load, and in sediment deposits. Clastic sedimentary rocks are rocks composed predominantly of broken pieces or clasts of older weathered and eroded rocks.
HypolimnionThe hypolimnion or under lake is the dense, bottom layer of water in a thermally-stratified lake. The word "hypolimnion" is derived from λιμνίον. It is the layer that lies below the thermocline. Typically the hypolimnion is the coldest layer of a lake in summer, and the warmest layer during winter. In deep, temperate lakes, the bottom-most waters of the hypolimnion are typically close to 4 °C throughout the year. The hypolimnion may be much warmer in lakes at warmer latitudes.
SaôneThe Saône (soʊn , son; Sona; Arar) is a river in eastern France. It is a right tributary of the Rhône, rising at Vioménil in the Vosges department and joining the Rhône in Lyon, at the southern end of the Presqu'île. The name Saône derives from that of the Gallic river goddess Souconna, which has also been connected with a local Celtic tribe, the Sequanes. Monastic copyists progressively transformed Souconna to Saoconna, which ultimately gave rise to Saône. The other recorded ancient names for the river were Brigoulus and Arar.
ArveThe Arve (L'Arve, aʁv) is a river in France (département of Haute-Savoie), and Switzerland (canton of Geneva). A left tributary of the Rhône, it is long, of which 9 km in Switzerland. Its catchment area is , of which 80 km2 in Switzerland. Its average discharge in Geneva is . Rising in the northern side of the Mont Blanc massif in the Alps, close to the Swiss border, it receives water from the many glaciers of the Chamonix valley (mainly the Mer de Glace) before flowing north-west into the Rhône on the west side of Geneva, where its much higher level of silt brings forth a striking contrast between the two rivers.
StormA storm is any disturbed state of the natural environment or the atmosphere of an astronomical body. It may be marked by significant disruptions to normal conditions such as strong wind, tornadoes, hail, thunder and lightning (a thunderstorm), heavy precipitation (snowstorm, rainstorm), heavy freezing rain (ice storm), strong winds (tropical cyclone, windstorm), wind transporting some substance through the atmosphere such as in a dust storm, among other forms of severe weather.
ThunderstormA thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorms are sometimes called thundershowers. Thunderstorms occur in a type of cloud known as a cumulonimbus. They are usually accompanied by strong winds and often produce heavy rain and sometimes snow, sleet, or hail, but some thunderstorms produce little precipitation or no precipitation at all.
Drainage basinA drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, the drainage divide, made up of a succession of elevated features, such as ridges and hills. A basin may consist of smaller basins that merge at river confluences, forming a hierarchical pattern. Other terms for a drainage basin are catchment area, catchment basin, drainage area, river basin, water basin, and impluvium.
Lake stratificationLake stratification is the tendency of lakes to form separate and distinct thermal layers during warm weather. Typically stratified lakes show three distinct layers: the epilimnion, comprising the top warm layer; the thermocline (or metalimnion), the middle layer, whose depth may change throughout the day; and the colder hypolimnion, extending to the floor of the lake. Every lake has a set mixing regime that is influenced by lake morphometry and environmental conditions.
EpilimnionThe epilimnion or surface layer is the top-most layer in a thermally stratified lake. The epilimnion is the layer that is most affected by sunlight, its thermal energy heating the surface, thereby making it warmer and less dense. As a result, the epilimnion sits above the deeper metalimnion and hypolimnion, which are colder and denser. Additionally, the epilimnion is typically has a higher pH and higher dissolved oxygen concentration than the hypolimnion. In the water column, the epilimnion sits above all other layers.
