First of all, oil supplies are determined by OPEC (Organization of the Petroleum Exporting Countries) is an intergovernmental organization oil demand supply market upstream downstream Vienna Austria. This means that the market of oil is in control by OPEC, since they can limit the supply and alter the prices and quantity of oil available in the market. Global oil supplies fell in August due to the the multilateral measures as well as unplanned outages. This means that, OPEC has been putting in place measures to ensure that there is excess stock of oil available, to control the market and make sure that oil supplies are always available in the market. Whereas, there are also occasions whereby there is shortages of oil, seen as unplanned outages. OPEC has also suffered a fall in output in August, due to the turmoil in Libya, that disrupted oil flows. This turmoil resulted in a plunge in the amount of oil available, since many countries are unable to produce oil due to the unexpected circumstances. This then leads to a fall in the supply of oil in the market, which is seen to be a very bad situation for OPEC. Oil supplies in US also decreased in August after Hurricane Harvey hampered the oil production, since refineries were shut down, these means that there are lesser resources available to produce oil, and fewer companies will be able to produce oil. Hence, supply of oil in the market is directly affected, and hence fall. With such situations occurring, the total number of sellers in the oil market is now reduced, as many companies and firms have to cease their production of oil, and hence putting oil production and supply from their companies to a halt. As the number of sellers in the market is a factor that affects supply, a decrease in number of sellers in market will directly causes oil supply to decrease. With the fall in the supply of oil in the market, this leads to a leftward shift in the oil supply curve. At the prevailing demand of the oil, the leftward shift of the curve, will result in the rise in the prices of oil available, as the equilibrium quantity of oil falls and the equilibrium price of oil increases. Hence, oil becomes less affordable for the firms and individuals requiring oil, for production as a raw material, or a daily product used by households.”Atkinson said that this shift in output had already been reflected by markets” America was hit by a hurricane, causing refineries to be closed down. When oil refineries closes down, it results in the fall in the supply of oil available. Hence, at prevailing demand of oil, it leads to an increase in the equilibrium price of oil. However, as the hurricane is clearing up, oil prices are slowly returning to normal. Since the supply of oil is regaining its stability, and hence, being able to reduce the shortage of oil and coping with the demand of the oil.