Time Difference Between Utc And Gmt

Often used interchangeably, UTC and GMT (Greenwich Mean Time) are slightly different. GMT is a local time zone where UTC is an international time standard. Based on the Prime Meridian, GMT was established as a local time zone at Greenwich, United Kingdom, in 1886 (long before computers and international time standards were concepts). This is why Eastern Standard Time is UTC-5 and Pacific Standard Time is UTC-7. The difference between a given time zone and UTC time is called the UTC offset. In other words, Eastern Standard Time has a UTC offset of minus 5 hours (UTC-5). But remember, UTC is a time standard. GMT, on the other hand, is a time zone.

What is UTC or GMT Time?

Weather observations around the world (including surface, radar, and other observations) are always taken with respect to a standard time. By convention, the world's weather communities use a twenty four hour clock, similar to 'military' time based on the 0° longitude meridian, also known as the Greenwich meridian.

Prior to 1972, this time was called Greenwich Mean Time (GMT) but is now referred to as Coordinated Universal Time orUniversal Time Coordinated (UTC). It is a coordinated time scale, maintained by the Bureau International des Poids etMesures (BIPM). It is also known as 'Z time' or 'Zulu Time'.

To obtain your local time here in the United States, you need to subtract a certain number of hours from UTC dependingon how many time zones you are away from Greenwich (England). The table below shows the standard difference from UTC time to local time.

The switch to daylight saving time does not affect UTC. It refers to time on the zero or Greenwich meridian, which is notadjusted to reflect changes either to or from Daylight Saving Time.

However, you need to know what happens during daylight saving time in the United States. Jitsi meet online. In short, the local time is advanced one hour during daylight saving time. As an example, the Eastern Time zone difference from UTC is -4 hours during daylight saving time rather than -5 hours as it is during standard time.

Standard TimeDaylight Saving
AST - Atlantic, AK - Alaska time, HI - Hawaii time, *The previous day, %The next day

Note: Credit given to NWS Southern Region Headquarters for the information above.

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Difference Between Gmt Utc And Zulu Time

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Between EDT and GMT, there is a difference of 4 hours. But, to understand how this is derived at, first let us see what EDT and GMT stand for and the purpose of having different time standards. EDT stands for Eastern Daylight Time while GMT stands for Greenwich Mean Time. EDT is followed to make the lives of humans easier while GMT is followed all around the world to let all of us keep accurate time. GMT is made according to astronomical observations. This is actually a country based time standard. In this article, we will discuss more about EDT and GMT and try to understand the difference between EDT and GMT.

What is GMT?

The world is divided into many time zones, and all places have a local time and also a time in relation with GMT, which is known as Greenwich Mean Time. Greenwich is a place in England from where all time zones in the world are measured. It is the Prime Meridian or Greenwich Meridian (longitude zero degrees) that is the starting point for all time zones in the world. GMT is also said to be World Time, and it sets the current time at all places of the world. Of late, however, it has been replaced by UTC (Coordinated Universal Time) that is based upon the atomic clock and considered to be more precise.

Earth’s zero degree line of longitude passes through Greenwich and is called Greenwich Meridian. If you are in a country east of GMT, you are ahead of the GMT. For example, local time in India is GMT + 5.5 hours. On the other hand, west of GMT, local time is behind GMT. If you are in NY, local time in summers is GMT – 4 hours and GMT- 5 hours in winters. As you can see, GMT + signifies that the time zone is east of GMT and GMT – signifies that the time zone is west of GMT.

Difference between gmt utc and zulu time

What is EDT?

EDT, on the other hand, is called Eastern Daylight Time and refers to a time zone that is 4 hours behind GMT or UTC. EDT is applied in eastern parts of US and Canada. It is used in the Caribbean too. In some record, it is also called as Eastern Daylight Savings Time, which is a system of saving time in a particular period of the year by advancing the clocks by an hour. EDT is mainly used in summers in the eastern part of North American Continent. EDT starts at 3 AM on the second Sunday of March (2 AM EST) and continues till the first Sunday of November. It ends on this day at 2 AM EDT, which gets converted to 1 AM EST. EDT is the current time in Greenwich minus four hours. It means that when it is noon at Greenwich, it is 8 AM in the EDT time zone.

EDT = GMT – 4 hours

Time Difference Between Utc And Gmt Time

What is the difference between EDT and GMT?

• GMT stands for Greenwich Mean Time.

• EDT stands for Eastern Daylight Time.

Time Difference Between Utc And Gmt Time Zone

• All the time zones around the world refer to GMT (now to UTC) when telling their time. Each time zone is either ahead of GMT or after GMT. The time zones that are ahead are the ones situated east to the Prime Meridian along which the GMT line is drawn. The time zones that are after GMT are the ones situated west to the Prime Meridian.

• EDT is a time zone that is 4 hours behind GMT or UTC.

Time Difference Between Utc And Gmt Now

Time Difference Between Utc And Gmt

• GMT is used all around the world. However, EDT is only used in the North America and the Caribbean.

• GMT is used all around the year. EDT is only used in the summer.

Difference Between Utc And Gmt Standard Time

Images Courtesy: UTC−04: Blue (January), Orange (July), Yellow (all year round), Light Blue – Sea areas via Wikicommons (Public Domain)

Difference Between Gmt And Utc Time Zone

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