Query: There may have been regions of Greenland that were 'greener' than today

Relevant passages:
Greenland <=SEP=> Greenland ( -LSB- ˈɡriːnlənd -RSB- Kalaallit Nunaat -LSB- kaˈlaːɬit ˈnunaːt -RSB- Grønland -LSB- ˈɡ̊ʁɶnˌlanˀ -RSB- ) is an autonomous constituent country within the Kingdom of Denmark between the Arctic and Atlantic Oceans , east of the Canadian Arctic Archipelago . Though physiographically a part of the continent of North America , Greenland has been politically and culturally associated with Europe ( specifically Norway and Denmark , the colonial powers , as well as the nearby island of Iceland ) for more than a millennium . The majority of its residents are Inuit , whose ancestors began migrating from the Canadian mainland in the 13th century , gradually settling across the island .   Greenland is the world 's largest island ( Australia , although larger , is generally considered to be a continental landmass rather than an island ) . Three-quarters of Greenland is covered by the only permanent ice sheet outside Antarctica . With a population of about 56,480 ( 2013 ) , it is the least densely populated country in the world . The Arctic Umiaq Line ferry acts as a lifeline for western Greenland , connecting the various cities and settlements .   Greenland has been inhabited off and on for at least the last 4,500 years by Arctic peoples whose forebears migrated there from what is now Canada . Norsemen settled the uninhabited southern part of Greenland beginning in the 10th century , and Inuit peoples arrived in the 13th century . The Norse colonies disappeared in the late 15th century . Soon after their demise , beginning in 1499 , the Portuguese briefly explored and claimed the island , naming it Terra do Lavrador ( later applied to Labrador in Canada ) . In the early 18th century , Scandinavian explorers reached Greenland again . To strengthen trading and power , Denmark-Norway affirmed sovereignty over the island .   Denmark -- Norway claimed Greenland for centuries . Greenland was settled by Vikings ( of Norwegian origin ) more than a thousand years ago , who had previously settled Iceland to escape persecution from the King of Norway and his central government . Vikings set sail from Greenland and Iceland , encountering North America nearly 500 years before Columbus reached the Caribbean islands . They attempted to colonize land . Though under continuous influence of Norway and Norwegians , Greenland was not formally under the Norwegian crown until 1262 . The Kingdom of Norway was extensive and a military power until the mid-14th century . Norway was dramatically hit with a larger death toll than Denmark by the Black Death , forcing Norway to accept a union in which the central government , university and other fundamental institutions were located in Copenhagen . Thus , the two kingdoms ' resources were directed at creating Copenhagen . Norway became the weaker part and lost sovereignty over Greenland in 1814 when the union was dissolved . Greenland became a Danish colony in 1814 , and was made a part of the Danish Realm in 1953 under the Constitution of Denmark .   In 1973 , Greenland joined the European Economic Community with Denmark . However , in a referendum in 1982 , a majority of the population voted for Greenland to withdraw from the EEC which was effected in 1985 . Greenland contains the world 's largest and most northernly national park , Northeast Greenland National Park ( Kalaallit Nunaanni nuna eqqissisimatitaq ) . Established in 1974 and expanded to its present size in 1988 , it protects 972001 km2 of the interior and northeastern coast of Greenland and is bigger than all but twenty-nine countries in the world . Greenland is divided into four municipalities - Sermersooq , Kujalleq , Qaasuitsup , and Qeqqata .   In 1979 , Denmark had granted home rule to Greenland , and in 2008 , Greenlanders voted in favour of the Self-Government Act , which transferred more power from the Danish royal government to the local Greenlandic government . Under the new structure , in effect since 21 June 2009 , Greenland can gradually assume responsibility for policing , judicial system , company law , accounting , and auditing ; mineral resource activities ; aviation ; law of legal capacity , family law and succession law ; aliens and border controls ; the working environment ; and financial regulation and supervision , while the Danish government retains control of foreign affairs and defence . It also retains control of monetary policy , providing an initial annual subsidy of DKK 3.4 billion , which is planned to diminish gradually over time . Greenland expects to grow its economy based on increased income from the extraction of natural resources . The capital , Nuuk , held the 2016 Arctic Winter Games . At 70 % , Greenland has one of the highest shares of renewable energy in the world , mostly coming from hydropower .

Sahara <=SEP=> The Sahara ( الصحراء الكبرى , , ` the Greatest Desert ' ) is the largest hot desert and the third largest desert in the world after Antarctica and the Arctic . Its area of 9200000 km2 is comparable to the area of the United States .   The desert comprises much of North Africa , excluding the fertile region on the Mediterranean Sea coast , the Atlas Mountains of the Maghreb , and the Nile Valley in Egypt and Sudan . It stretches from the Red Sea in the east and the Mediterranean in the north to the Atlantic Ocean in the west , where the landscape gradually changes from desert to coastal plains . To the south , it is bounded by the Sahel , a belt of semi-arid tropical savanna around the Niger River valley and the Sudan Region of Sub-Saharan Africa .   The Sahara can be divided into several regions including : the western Sahara , the central Ahaggar Mountains , the Tibesti Mountains , the Aïr Mountains , the Ténéré desert , and the Libyan Desert .   The name ` Sahara ' is derived from ( , pronounced -LSB- / / ˈSaHa : ra : -RSB- ) , the plural of the Arabic word for `` desert '' .

Greenland ice sheet <=SEP=> The Greenland ice sheet ( Grønlands indlandsis , Sermersuaq ) is a vast body of ice covering 1710000 km ² , roughly 80 % of the surface of Greenland .   It is the second largest ice body in the world , after the Antarctic ice sheet . The ice sheet is almost 2400 km long in a north-south direction , and its greatest width is 1100 km at a latitude of 77 ° N , near its northern margin . The mean altitude of the ice is 2135 m . The thickness is generally more than 2 km and over 3 km at its thickest point . It is not the only ice mass of Greenland -- isolated glaciers and small ice caps cover between 76000 and around the periphery . If the entire 2850000 km3 of ice were to melt , it would lead to a global sea level rise of 7.2 m . The Greenland Ice Sheet is sometimes referred to under the term inland ice , or its Danish equivalent , indlandsis . It is also sometimes referred to as an ice cap .

Reforestation <=SEP=> Reforestation is the natural or intentional restocking of existing forests and woodlands that have been depleted , usually through deforestation . Reforestation can be used to rectify or improve the quality of human life by soaking up pollution and dust from the air , rebuild natural habitats and ecosystems , mitigate global warming since forests facilitate biosequestration of atmospheric carbon dioxide , and harvest for resources , particularly timber , but also non-timber forest products .   The term reforestation is similar to afforestation , the process of restoring and recreating areas of woodlands or forests that may have existed long ago but were deforested or otherwise removed at some point in the past . Sometimes the term re-afforestation is used to distinguish between the original forest cover and the later re-growth of forest to an area . Forestation is the establishment of forest growth on areas that either had forest or lacked it .   Special tools , e.g. tree planting bars , are used to make planting of trees easier and faster .