July 2015 was very likely Earth’s hottest month on record

The warmest year on record so far may have claimed another milestone, and this time it’s a big one.

According to preliminary data from NASA along with information from the Japan Meteorological Administration, July 2015 was the warmest month on record since instrument temperature records began in the late 1800s.

Research using other data, such as tree rings, ice cores and coral formations in the ocean, have shown that the Earth is now the warmest it has been since at least 4,000 years ago.

According to NASA’s data, which is subject to refinement in coming weeks and months as more is analyzed, July 2015’s average temperature nudged past July 2011 by 0.02 degrees Celsius, or .36 degrees Fahrenheit.

Every month this year has ranked in the top four warmest months, according to NASA’s data.

July is typically the hottest month on Earth, due to the peak of heating in the Northern Hemisphere, which has a far greater land area than the Southern Hemisphere.

The National Oceanic and Atmospheric Administration (NOAA), has not yet released its monthly temperature data for July, but it is likely to also report that July was in the top 4 warmest Julys, if not the warmest July and warmest month, period, the globe has yet seen.

NASA, the NOAA and other agencies use different methods of analysis to compute monthly and annual averages and rank years, although there is considerable overlap between the data sets each agency uses.

In the Japan Meteorological Agency’s data, five of seven months so far this year have ranked warmest on record, including July. The JMA, NASA and NOAA have all shown that 2015 is on track to beat last year for the title of the warmest year on record.

In order for 2015 not to be the warmest year on record, the rest of the year would have to turn sharply colder, on a global average. That is not likely to happen, considering both the influence of long-term manmade global warming and a shorter-term climate cycle known as El Niño.

According to forecasters at NOAA, the ongoing El Niño event, which is characterized by much warmer than average ocean temperatures across the equatorial tropical Pacific Ocean, is now expected to be among the strongest ever observed.

One of the many side effects of El Niño is that the added heat from the ocean and atmosphere tends to boost global average surface temperatures. The record El Niño of 1997-98 led 1998 to become the hottest year on record, until it was eclipsed by 2014’s record warmth, which remarkably occurred in the absence of an officially declared El Niño.

News comes as Western U.S. bakes and burns

The hottest July milestone comes as the U.S. government mobilizes military units to help respond to an escalating outbreak of wildfires throughout the West, much of which is tinderbox-dry and scorchingly hot.

Image: Les Zaitz/The Oregonian/OregonLive via AP/Associated Press

More than 14,000 firefighters were battling blazes in California alone as of Monday morning, with large, destructive blazes also burning in Washington, Idaho and Oregon as drought conditions intensify in those states.

California is suffering through its worst drought in a millennium, and its hottest year so far.

Climate studies show that while global warming may not have caused this drought, it likely made it worse by elevating temperatures, which exacerbates evaporation and dries soils out faster.

The July milestone also comes in the midst of a summer of deadly, record-shattering heat around the world, from North America to South Asia.

While heat waves are synonymous with summer, the heat this year has set all-time records — which are rarely eclipsed to the extent that they have been in 2015.

Such temperature records have fallen on several continents. That makes the summer of 2015 stand out from others that featured record-smashing and deadly heat events, such as 2003, when an August heat wave killed more than 40,000 in Europe.

Extreme heat has been blamed for thousands of deaths from India to Egypt, into Europe and west to the Pacific Northwest cities of Seattle and Portland. Even Japan and Hong Kong have set all-time high temperature records and passed historical heat wave markers.

The heat waves began in June before the Indian Monsoon kicked into gear, as high temperatures well into the triple digits Fahrenheit hit India and Pakistan, killing more than 2,000 people.

Madrid, for example, set monthly high temperature records in both June and July, with a record high temperature on July 6 of 103.8 degrees Fahrenheit, or 39.9 degrees Celsius.

Germany broke its all-time heat record on July 5, when the temperature reached 104.5 degrees Fahrenheit, or 40.3 degrees Celsius, in Kitzingen, according to Germany’s National Meteorological Service. The U.K. set an all-time July heat record when the temperature at London’s Heathrow Airport reached 98.1 degrees Fahrenheit, or 36.7 degrees Celsius, on July 1, according to the Met Office.

Maastricht in the Netherlands, set a new national July heat record in July, when the temperature reached 100.8 degrees Fahrenheit, or 38.2 degrees Celsius, according to the Weather Channel.

Published scientific research shows that manmade global warming is very likely playing an integral role in intensifying, and possibly also triggering, these extreme heat events.

Thoughts and prayers are with those affected by the wildfires in the Northwest. pic.twitter.com/q6yqb697bN

— Kjell Lindgren (@astro_kjell) August 17, 2015

A study published in April in the journal Nature Climate Change found that the probability of 1-in-1,000-day hot extremes over land is already about five times higher than it was in pre-industrial times, when global average surface temperatures were lower. To put it another way, the study found that about 75% of “those moderate hot extremes are attributable to warming.”

The study, along with many others, found that the probability of hot extremes is likely to increase significantly as global warming continues.

World leaders will convene in Paris starting on November 30 to forge a new climate change agreement that would limit greenhouse gas emissions after the year 2020. So far, the amount of emissions cuts pledged by countries including the U.S., China, European Union and Brazil do not add up to enough to limit global warming below the agreed upon guardrail: 2 degrees Celsius, or 3.6 degrees Fahrenheit, above preindustrial levels by 2100.

If Earth continues on its current emissions path, it is already headed for warming of up to 9 degrees Fahrenheit by the end of the century — which few climate scientists argue would be anything other than catastrophic. A drastic rise in sea levels, heat waves, species extinctions and shifts in extreme weather events would result.

In other words, this July record could be viewed as a warning of what may be in store depending on decisions made very soon.