It's official, 2014 has been named the warmest year on record, with records beginning in 1880 based on a study done by NASA and the National Oceanic and Atmospheric Association (NOAA). The global temperature in 2014 was 1.24°F higher than the 20th century average. The global temperature is the average between ocean and land temperatures. Average global land temperatures were 1.80°F above the 20th century average, making it the 4th warmest on record. Average global sea temperatures were 1.03°F above the 20th century average making it the record warmest since 1880. While 1° doesn't sound like a big difference, it is in terms of a global average. When you think about how big the planet is, it takes a lot of energy to move the global average up or down, it also takes more energy to change the temperature of the ocean compared to land.
The global average has been trending upwards since 1880, despite year-to-year fluctuations. Large scale weather patterns and events like El Nino and La Nina will have an effect on that year's average. While El Nino is a pattern that warms the tropics, 2014 was actually an El Nino neutral year.
You also might remember how cold last year was for us in the Midwest, it was also unusually cool for the East Coast; but places like the West Coast and Alaska experienced their warmest years on record. That is because regional differences are affected by weather dynamics and not so much the global mean. So while it was a frigid winter for us and a fairly mild summer, many other places had to deal with the heat.
Climate dynamics is very complex and there are a lot of variables that go into regional and global patterns and warming trends. To read more about 2014 you can visit NASA's website or NOAA's.