Query: For the year-to-date, the Earth is seeing its 5th-warmest start to the year.

Relevant passages:
Earth <=SEP=> Earth ( from Eorðe -LSB- Γαῖα , Gaia -RSB- Terra ) , otherwise known as the World or the Globe , is the third planet from the Sun and the only object in the Universe known to harbor life . It is the densest planet in the Solar System and the largest of the four terrestrial planets .   According to radiometric dating and other sources of evidence , Earth formed about 4.54 billion years ago . Earth 's gravity interacts with other objects in space , especially the Sun and the Moon , Earth 's only natural satellite . During one orbit around the Sun , Earth rotates about its axis over 365 times ; thus , an Earth year is about 365.26 days long . Earth 's axis of rotation is tilted , producing seasonal variations on the planet 's surface . The gravitational interaction between the Earth and Moon causes ocean tides , stabilizes the Earth 's orientation on its axis , and gradually slows its rotation .   Earth 's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years . About 71 % of Earth 's surface is covered with water , mostly by its oceans . The remaining 29 % is land consisting of continents and islands that together have many lakes , rivers and other sources of water that contribute to the hydrosphere . The majority of Earth 's polar regions are covered in ice , including the Antarctic ice sheet and the sea ice of the Arctic ice pack . Earth 's interior remains active with a solid iron inner core , a liquid outer core that generates the Earth 's magnetic field , and a convecting mantle that drives plate tectonics .   Within the first billion years of Earth 's history , life appeared in the oceans and began to affect the Earth 's atmosphere and surface , leading to the proliferation of aerobic and anaerobic organisms . Some geological evidence indicates that life may have arisen as much as 4.1 billion years ago . Since then , the combination of Earth 's distance from the Sun , physical properties , and geological history have allowed life to evolve and thrive . In the history of the Earth , biodiversity has gone through long periods of expansion , occasionally punctuated by mass extinction events . Over 99 % of all species that ever lived on Earth are extinct . Estimates of the number of species on Earth today vary widely ; most species have not been described . Over 7.4 billion humans live on Earth and depend on its biosphere and minerals for their survival . Humans have developed diverse societies and cultures ; politically , the world has about 200 sovereign states .

New Year <=SEP=> New Year is the time at which a new calendar year begins and the calendar 's year count increments by one .   Many cultures celebrate the event in some manner and the 1st day of January is often marked as a national holiday .   In the Gregorian calendar , the most widely used calendar system today , New Year occurs on 1 January ( New Year 's Day ) . This was also the case both in the old Roman calendar ( at least after about 713 BCE ) and in the Julian calendar that succeeded it .   Other calendars have been used historically in different parts of the world ; some calendars count years numerically , while others do not .   During the Middle Ages in western Europe , while the Julian calendar was still in use , authorities moved New Year 's Day variously , depending upon locale , to one of several other days , among them : 1 March , 25 March , Easter , 1 September , and 25 December . Beginning in 1582 , the adoptions of the Gregorian calendar and changes to the Old Style and New Style dates meant the various local dates for New Year 's Day changed to using one fixed date , January 1 .   The widespread official adoption of the Gregorian calendar and marking January 1 as the beginning of a new year is almost global now . Regional or local use of other calendars continue , along with the cultural and religious practices that accompany them . In Latin America , various native cultures continue the observation of traditions according to their own calendars . Israel , China , India and other countries , continue to celebrate New Year on different dates .   The most common dates of modern New Year 's celebrations are listed below , ordered and grouped by their alignment relative to the Gregorian calendar .

Tropical year <=SEP=> A tropical year ( also known as a solar year ) , for general purposes , is the time that the Sun takes to return to the same position in the cycle of seasons , as seen from Earth ; for example , the time from vernal equinox to vernal equinox , or from summer solstice to summer solstice . Because of the precession of the equinoxes , the seasonal cycle does not remain exactly synchronized with the position of the Earth in its orbit around the Sun . As a consequence , the tropical year is about 20 minutes shorter than the time it takes Earth to complete one full orbit around the Sun as measured with respect to the fixed stars ( the sidereal year ) .   Since antiquity , astronomers have progressively refined the definition of the tropical year . The entry for `` year , tropical '' in the Astronomical Almanac Online Glossary 2015 states :   the period of time for the ecliptic longitude of the Sun to increase 360 degrees . Since the Sun 's ecliptic longitude is measured with respect to the equinox , the tropical year comprises a complete cycle of seasons , and its length is approximated in the long term by the civil ( Gregorian ) calendar . The mean tropical year is approximately 365 days , 5 hours , 48 minutes , 45 seconds .   An equivalent , more descriptive , definition is `` The natural basis for computing passing tropical years is the mean longitude of the Sun reckoned from the precessionally moving equinox ( the dynamical equinox or equinox of date ) . Whenever the longitude reaches a multiple of 360 degrees the mean Sun crosses the vernal equinox and a new tropical year begins '' . ( Borkowski 1991 , p. 122 )   The mean tropical year in 2000 was 365.24219 ephemeris days ; each ephemeris day lasting 86,400 SI seconds . This is 365.24217 mean solar days . ( Richards , 2013 , p. 587 )

Year <=SEP=> A year is the orbital period of the Earth moving in its orbit around the Sun . Due to the Earth 's axial tilt , the course of a year sees the passing of the seasons , marked by changes in weather , the hours of daylight , and , consequently , vegetation and soil fertility . In temperate and subpolar regions around the globe , four seasons are generally recognized : spring , summer , autumn and winter . In tropical and subtropical regions several geographical sectors do not present defined seasons ; but in the seasonal tropics , the annual wet and dry seasons are recognized and tracked .   A calendar year is an approximation of the number of days of the Earth 's orbital period as counted in a given calendar . The Gregorian , or modern , calendar , presents its calendar year to be either a common year of 365 days or a leap year of 366 days , as do the Julian calendars ; see below . For the Gregorian calendar the average length of the calendar year ( the mean year ) across the complete leap cycle of 400 years is 365.2425 days . The ISO standard ISO 80000-3 , Annex C , supports the symbol `` a '' ( for Latin annus ) to represent a year of either 365 or 366 days . In English , the abbreviations `` y '' and `` yr '' are commonly used .   In astronomy , the Julian year is a unit of time ; it is defined as 365.25 days of exactly seconds ( SI base unit ) , totalling exactly seconds in the Julian astronomical year .   The word `` year '' is also used for periods loosely associated with , but not identical to , the calendar or astronomical year , such as the seasonal year , the fiscal year , the academic year , etc. . Similarly , `` year '' can mean the orbital period of any planet : for example , a Martian year or a Venusian year are examples of the time a planet takes to transit one complete orbit . The term can also be used in reference to any long period or cycle , such as the Great Year .