Fourteen of 15 Hottest Years Have Been in 21st Century

A press release from the World Meteorological Organization: The World Meteorological Organization (WMO) has ranked 2014 as the hottest year on record, as part of a continuing trend. After consolidating leading international datasets, WMO noted that the difference in temperature between the warmest years is only a few hundredths of a degree – less than the margin of uncertainty.

Average global air temperatures over land and sea surface in 2014 were 0.57 °C (1.03°F) above the long-term average of 14.00°C (57.2 °F) for the 1961-1990 reference period. By comparison, temperatures were 0.55 °C (1.00°F) above average in 2010 and 0.54°C (0.98°F) above average in 2005,  according to WMO calculations. The estimated margin of uncertainty was 0.10°C (0.18°F).

“The overall warming trend is more important than the ranking of an individual year,” said WMO Secretary-General Michel Jarraud. “Analysis of the datasets indicates that 2014 was nominally the warmest on record, although there is very little difference between the three hottest years,” said Mr Jarraud.

“Fourteen of the fifteen hottest years have all been this century. We expect global warming to continue, given that rising levels of greenhouse gases in the atmosphere and the increasing heat content of the oceans are committing us to a warmer future,” he said. Around 93% of the excess energy trapped in the atmosphere by greenhouse gases from fossil fuels and other human activities ends up in the oceans. Therefore, the heat content of the oceans is key to understanding the climate system. Global sea-surface temperatures reached record levels in 2014.[1]

It is notable that the high 2014 temperatures occurred in the absence of a fully developed El Niño. El Niño occurs when warmer than average sea-surface temperatures in the eastern tropical Pacific combine, in a self-reinforcing loop, with atmospheric pressure systems. This has an overall warming impact on the climate. High temperatures in 1998 – the hottest year before the 21st century – occurred during a strong El-Niño year....

Graph from the WMO website

2011 as 11th confirmed warmest on record

World Meteorological Organization: The World Meteorological Organization’s Annual Statement on the Status of the Global Climate said that 2011 was the 11th warmest since records began in 1850. It confirmed preliminary findings that 2011 was the warmest year on record with a La Niña, which has a cooling influence. Globally-averaged temperatures in 2011 were estimated to be 0.40° Centigrade above the 1961-1990 annual average of 14°C.

Precipitation extremes, many of them associated with one of the strongest La Niña events of the last 60 years, had major impacts on the world. Significant flooding occurred on all continents, whilst major droughts affected parts of east Africa and North America. Arctic sea ice extent fell to near record-low levels. Global tropical cyclone activity was below average, but the United States had one of its most destructive tornado seasons on record.

The annual statement for 2011 was released for World Meteorological Day 23 March. In addition, WMO also announced preliminary findings of the soon to be released Decadal Global Climate Summary, showing that climate change accelerated in 2001-2010, which was the warmest decade ever recorded in all continents of the globe.

The rate of increase since 1971 has been “remarkable” according to the preliminary assessment. Atmospheric and oceanic phenomena such as La Niña events had a temporary cooling influence in some years but did not halt the overriding warming trend.

The “dramatic and continuing sea ice decline in the Arctic” was one of the most prominent features of the changing state of the climate during the decade, according to the preliminary findings. Global average precipitation was the second highest since 1901 and flooding was reported as the most frequent extreme event, it said....

Better climate services would improve drought management

A press release from the World Meteorological Organization: Scientific progress has laid the basis for more effective policies to combat and manage drought and desertification. The challenge of climate change means it is imperative to translate that science into action, according to the World Meteorological Organization.

...[WMO Secretary General Michel] Jarraud outlined the plans for the new Framework during the High-Level Segment of the Tenth session of the Conference of the Parties of the UN Convention to Combat Desertification (UNCCD) in Changwon, Republic of Korea. He addressed a Roundtable entitled “Harnessing Science Knowledge for combating desertification, land degradation and drought: The path to improvement”....In his presentation to the UNCCD Roundtable, Mr Jarraud made the following points:

• Even without the recent climate change concern, land degradation is especially critical as only around 11% of the global land surface feeds a population of some 7 billion.
• The picture is even grimmer if we include the cumulative effects (since 1750) of greenhouse gases from human activities (fossil fuel burning & land use).
• ...in different areas there might either be augmented land degradation, due to drought, or increased soil erosion, owing to enhanced rainfall....
• ... by altering the familiar spatial and temporal patterns of temperature, rainfall, solar radiation and winds, climate change will contribute to exacerbate desertification, so societies should recognize that historic/ traditional knowledge can often no longer be accepted as a valid indicator of the future.

WMO plans aeronautical meteorology programme

ABC Live (India): The World Meteorological Organization plans to boost its aeronautical meteorological activities given their importance to safe, regular and efficient air navigation. The World Meteorological Congress has decided to make the Aeronautical Meteorology Programme a ‘’high-priority programme that should be suitably resourced” to help its Members meet the increasing needs of the aviation sector.

“The recent eruptions of the Eyjafjallajökull and Grímsvötn volcanoes in Iceland served as a reminder of the importance of aeronautical meteorology in predicting and projecting the spread of the volcanic ash cloud, and providing authoritative information to civil aviation authorities to help inform their decisions,” said WMO Secretary-General Michel Jarraud.

“The rapid growth in air traffic requires increased levels of aeronautical meteorological services. Given the strong linkage between flight delays and poor weather conditions in terms of low visibility, turbulence, icing and severe convection, aeronautical meteorology services are key for authorities who need to take decisions that minimize disruption to travel, whilst ensuring passenger safety,” said Mr Jarraud.

Aviation meteorology is the main source of income, through cost recovery, for many National Meteorological Services, particularly in developing countries. There is constant pressure within the aviation sector for increased efficiency in the provision of external services including meteorology.

…WMO’s Aeronautical Meteorology Programme promotes technology transfer, education and training, and capacity building to help National Meteorological Services, particularly in developing countries, meet the needs of international and national civil air navigation authorities….

An Airbus A320, shot by Montgomery, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license