A tourist cools off his head into a fountain in Rome’s People Square, Friday, as temperatures are expected to reach 38 degrees Celsius (100.4 Fahrenheit) over the weekend in central and northern Italy. (AP)

WASHINGTON (REUTERS) – The world is enduring the hottest year on record, according to a U.S. national weather analysis, causing droughts worldwide and a concern for U.S. farmers counting on another bumper year.

For the first six months of the year, 2010 has been warmer than the first half of 1998, the previous record holder, by 0.03 degree Fahrenheit, said Jay Lawrimore, chief of climate analysis at the federal National Climatic Data Center.

Period of a El Niño weather pattern is being blamed for the hot temperatures globally.

"We had an El Niño episode in the early part of the year that's now faded but that has contributed to the warmth not only in equatorial Pacific but also contributed to anomalously warm global temperatures as well," Lawrimore said.

Abnormally warm temperatures have been registered in large parts of Canada, Africa, tropical oceans and parts of the Middle East.

Northern Thailand is struggling through the worst drought in 20 years, while Israel is in the middle of the longest and most severe drought since 1920s. In Britain, this year has been the driest since 1929.

Also, Arctic sea ice has melted to its thinnest state in June.

However, as cooler temperatures may set in later this year, it remains to be seen whether 2010 will overtake 2005 as the hottest year overall.

"This year the fact that the El Niño episode has ended and is likely to transition into La Niña, which has a cooling influence on the global average temperature, it's possible that we will not end up with the warmest year as a whole."