Autumn leaf color in the context of "Yellow"

Autumn, also known as fall in North American English, is one of the four temperate seasons on Earth. Outside the tropics, autumn marks the transition from summer to winter, beginning in September (Northern Hemisphere) or March (Southern Hemisphere). Autumn is the season when the duration of daytime becomes noticeably shorter and the temperature cools considerably. Day length decreases and night length increases as the season progresses until the winter solstice in December (Northern Hemisphere) and June (Southern Hemisphere). One of its main features in temperate climates is the striking change in colour of the leaves of deciduous trees as they prepare to shed.

Carotenoids (/kəˈrɒtɪnɔɪd/) are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, archaea, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, corn, tomatoes, canaries, flamingos, salmon, lobster, shrimp, and daffodils. Over 1,100 identified carotenoids can be further categorized into two classes – xanthophylls (which contain oxygen) and carotenes (which are purely hydrocarbons and contain no oxygen).

All are derivatives of tetraterpenes, meaning that they are produced from 8 isoprene units and contain 40 carbon atoms. In general, carotenoids absorb wavelengths ranging from 400 to 550 nanometers (violet to green light). This causes the compounds to be deeply colored yellow, orange, or red. Carotenoids are the dominant pigment in autumn leaf coloration of about 15-30% of tree species, but many plant colors, especially reds and purples, are due to polyphenols.

In Japanese architecture, fusuma (襖) are vertical rectangular panels which can slide from side to side to redefine spaces within a room, or act as doors. They typically measure about 90 cm (2 ft 11 in) wide by 180 cm (5 ft 11 in) tall, the same size as a tatami mat, and are 2–3 cm (0.79–1.18 in) thick. The heights of fusuma have increased in recent years due to an increase in average height of the Japanese population, and a 190 cm (6 ft 3 in) height is now common. In older constructions, they are as small as 170 cm (5 ft 7 in) high. They consist of a lattice-like wooden understructure covered in cardboard and a layer of paper or cloth on both sides. They typically have a black lacquer border and a round finger catch.

Historically, fusuma were painted, often with scenes from nature such as mountains, forests or animals. Today, many feature plain mulberry paper, or have industrially-printed graphics of fans, autumn leaves, cherry blossom, trees, or geometric graphics. Patterns for children featuring popular characters can also be purchased.

Çamlıhemşin, formerly Vice, (Laz: ვიჯა Vija Laz pronunciation: [ˈvid͡ʒa] or Laz: ვიჯე Vije Laz pronunciation: [ˈvid͡ʒe]; Georgian: ვიჯა Vija Georgian pronunciation: [vid͡ʒa]) is a small town in Rize Province in the Black Sea region of Turkey. It is the seat of Çamlıhemşin District. Its population is 1,763 (2021).

With its mountains and valleys in all shades of green, Çamlıhemşin has a reputation as one of the most attractive parts of the eastern Black Sea region according to CNN, particularly during and thanks to its autumn foliage.