Viaduc de Millauvignette|Les sept paires de nappes de haubans du viaduc de Millau. vignette|Chaussée droite du viaduc bordée par l'écran brise-vent d'un côté et la nappe axiale de haubans de l'autre. vignette|Le tablier est suspendu par des câbles issus de pylônes. Le viaduc de Millau est un pont à haubans franchissant la vallée du Tarn, dans le département de l'Aveyron, en France. Portant l’A75, il assure la jonction entre le causse Rouge et le causse du Larzac en franchissant une brèche de de longueur et de de profondeur au point le plus haut, dans un panorama de grande qualité et avec des vents susceptibles de souffler à plus de .
Carbon dioxide in Earth's atmosphereIn Earth's atmosphere, carbon dioxide is a trace gas that plays an integral part in the greenhouse effect, carbon cycle, photosynthesis and oceanic carbon cycle. It is one of several greenhouse gases in the atmosphere of Earth. The current global average concentration of CO2 in the atmosphere is (0.04%) 421 ppm as of May 2022. This is an increase of 50% since the start of the Industrial Revolution, up from 280 ppm during the 10,000 years prior to the mid-18th century. The increase is due to human activity.
Secular variationThe secular variation of a time series is its long-term, non-periodic variation (see decomposition of time series). Whether a variation is perceived as secular or not depends on the available timescale: a variation that is secular over a timescale of centuries may be a segment of what is, over a timescale of millions of years, a periodic variation. Natural quantities often have both periodic and secular variations. Secular variation is sometimes called secular trend or secular drift when the emphasis is on a linear long-term trend.
