Query: The sun has gone into ‘lockdown’ which could cause freezing weather, earthquakes and famine, say scientists

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Famine <=SEP=> A famine is a widespread scarcity of food , caused by several factors including crop failure , population imbalance , or government policies . This phenomenon is usually accompanied or followed by regional malnutrition , starvation , epidemic , and increased mortality . Every inhabited continent in the world has experienced a period of famine throughout history . In the 19th and 20th century , it was generally Eastern Europe and Asia that suffered the most deaths from famine . The numbers dying from famine began to fall sharply from the 1970s .   Some countries , particularly in sub-Saharan Africa , continue to have extreme cases of famine . Since 2010 , Africa has been the most affected continent in the world . As of 2017 , the United Nations has warned some 20 million are at risk in South Sudan , Somalia , Nigeria and Yemen . Agricultural conditions have been fluctuating more and more due to variations in weather , and the distribution of food has been affected by conflict . Most programmes now direct their aid towards Africa .

Winter <=SEP=> Winter is the coldest season of the year in polar and temperate climates , between autumn and spring . Winter is caused by the axis of the Earth in that hemisphere being oriented away from the Sun . Different cultures define different dates as the start of winter , and some use a definition based on weather . When it is winter in the Northern Hemisphere , it is summer in the Southern Hemisphere , and vice versa . In many regions , winter is associated with snow and freezing temperatures . The moment of winter solstice is when the sun 's elevation with respect to the North or South Pole is at its most negative value ( that is , the sun is at its farthest below the horizon as measured from the pole ) , meaning this day will have the shortest day and the longest night . The earliest sunset and latest sunrise dates outside the polar regions differ from the date of the winter solstice , however , and these depend on latitude , due to the variation in the solar day throughout the year caused by the Earth 's elliptical orbit ( see earliest and latest sunrise and sunset ) .

Weather <=SEP=> Weather is the state of the atmosphere , to the degree that it is hot or cold , wet or dry , calm or stormy , clear or cloudy . Most weather phenomena occur in the lowest level of the atmosphere , the troposphere , just below the stratosphere . Weather refers to day-to-day temperature and precipitation activity , whereas climate is the term for the averaging of atmospheric conditions over longer periods of time . When used without qualification , `` weather '' is generally understood to mean the weather of Earth .   Weather is driven by air pressure , temperature and moisture differences between one place and another . These differences can occur due to the sun 's angle at any particular spot , which varies with latitude . The strong temperature contrast between polar and tropical air gives rise to the largest scale atmospheric circulations : the Hadley Cell , the Ferrel Cell , the Polar Cell , and the jet stream . Weather systems in the mid-latitudes , such as extratropical cyclones , are caused by instabilities of the jet stream flow . Because the Earth 's axis is tilted relative to its orbital plane , sunlight is incident at different angles at different times of the year . On Earth 's surface , temperatures usually range ± 40 ° C ( − 40 ° F to 100 ° F ) annually . Over thousands of years , changes in Earth 's orbit can affect the amount and distribution of solar energy received by the Earth , thus influencing long-term climate and global climate change .   Surface temperature differences in turn cause pressure differences . Higher altitudes are cooler than lower altitudes as most atmospheric heating is due to contact with the Earth 's surface while radiative losses to space are mostly constant . Weather forecasting is the application of science and technology to predict the state of the atmosphere for a future time and a given location . The Earth 's weather system is a chaotic system ; as a result , small changes to one part of the system can grow to have large effects on the system as a whole . Human attempts to control the weather have occurred throughout history , and there is evidence that human activities such as agriculture and industry have modified weather patterns .   Studying how the weather works on other planets has been helpful in understanding how weather works on Earth . A famous landmark in the Solar System , Jupiter 's Great Red Spot , is an anticyclonic storm known to have existed for at least 300 years . However , weather is not limited to planetary bodies . A star 's corona is constantly being lost to space , creating what is essentially a very thin atmosphere throughout the Solar System . The movement of mass ejected from the Sun is known as the solar wind .