It’s harvest time again in most European wine regions, with grapes being harvested from the UK in the north to Sicily in the south. The grapes are then sorted and pressed to produce the best possible juices. These juices will then be fermented in the barrel of your choice, be it oak, concrete, clay or stainless steel, to prepare the wine for spring blending and bottling. The harvest determines the vintage, while changes in weather lead to changes in the appeal of wines. My colleagues and I have published new research , which examines this variation and examines how temperature and precipitation affect quality. The quality is assessed in the spring when the wine is finished in the barrel ready for bottling. The French refer to this stage as en primeur (first) and at this time a futures market is formed where speculators and commercial buyers can buy wine in advance. First time they started Bordeaux wine merchants in the 1950s as a post-war way of providing money to financially struggling chateaux while the wine was still being bottled. The phenomenon has since spread throughout Europe. ( Andrew Wood from Oxford University)