Loch Lomond

Shown within Loch Lomond and The Trossachs National Park Loch Lomond (/ˈlɒx ˈloʊmənd/; Scottish Gaelic: Loch Laomainn) is a freshwater Scottish loch that spans the Highland Boundary Fault, often considered the boundary between the Lowlands and Highlands of Scotland. Traditionally forming part of the boundary between the counties of Stirlingshire and Dunbartonshire, it is today split between the council areas of Stirling, Argyll and Bute and West Dunbartonshire. Its southern shores are about 23 kilometres (14 mi) northwest of the centre of Glasgow, Scotland's largest city. The loch forms part of Loch Lomond and The Trossachs National Park, which was established in 2002. From a limnological perspective, Loch Lomond is classified as a dimictic lake, meaning it typically undergoes two mixing periods each year. This occurs in the spring and autumn when the water column becomes uniformly mixed due to temperature-driven density changes

Loch Lomond is 36.4 kilometres (22.6 mi) long and between one and eight kilometres (1⁄2–5 miles) wide, with a surface area of 71 km (27.5 mi). It is the largest lake in Great Britain by surface area; in the United Kingdom, it is surpassed only by Lough Neagh and Lough Erne in Northern Ireland. The loch has a maximum depth of about 190 metres (620 ft) in the deeper northern portion, although the southern part of the loch rarely exceeds 30 metres (98 ft) in depth. The total volume of Loch Lomond is 2.6 km (0.62 cu mi), making it the second largest lake in Great Britain, after Loch Ness, by water volume. Due to its considerable depth and latitudinal location, Loch Lomond exhibits thermal stratification during the summer months, with a distinct epilimnion, metalimnion, and hypolimnion forming in deeper areas. These stratification patterns have important implications for nutrient cycling and aquatic ecology within the loch. During periods of stratification, a decrease in hypolimnetic oxygen can occur in the deeper northern basin, which can affect the species distribution patterns.