The histograms all show similar
average warming trends and the stations with the longest measurement durations show the least dispersion of temperature trends.
Overall, UHI effects contribute 24.2 % to regional
average warming trends.
In order to make the trends comparable despite the different periods and CO2 increases, they were divided by the globally
averaged warming trend, i.e. all values above 1 show an above - average warming (orange - red), values below 1 a below - average warming, negative values a cooling.
Christy is correct to note that the model
average warming trend (0.23 °C / decade for 1978 - 2011) is a bit higher than observations (0.17 °C / decade over the same timeframe), but that is because over the past decade virtually every natural influence on global temperatures has acted in the cooling direction (i.e. an extended solar minimum, rising aerosols emissions, and increased heat storage in the deep oceans).
And I also agree that it is likely that the long - time
average warming trend of 0.05 C per decade will resume.
For the thirty - year period 1979 to 2009 (sometimes updated through 2010 or 2011), the various observational datasets find, in the tropical lower troposphere (LT, see Chapter 2 for definition),
an average warming trend ranging from 0.07 °C to 0.15 °C per decade.
So all these alarmists on here, man up, show some balls and faith in your statements and tell us by what years in this century will
the average warming trend hit 4 - 5 times, 3 times, twice, and even reach the 20 the century warming rate?
This analysis samples the ocean to 700 m depth and gives
an average warming trend of 0.64 W m − 2 (red line).
Not exact matches
If
average warming is instead caused by increased carbon dioxide, then a cooling
trend is unlikely to start on its own.
Most climatologists expect that on
average the atmospheres water vapor content will increase in response to surface
warming caused by the long - lived greenhouse gases, further accelerating the overall
warming trend.
While Mora's models, based on yearly
average temperatures, don't forecast monthly highs, lows or precipitation changes, they do show
warming trends.
In its annual analysis of
trends in global carbon dioxide emissions, the Global Carbon Project (GCP) published three peer - reviewed articles identifying the challenges for society to keep global
average warming less than 2 °C above pre-industrial levels.
While 2014 temperatures continue the planet's long - term
warming trend, scientists still expect to see year - to - year fluctuations in
average global temperature caused by phenomena such as El Niño or La Niña.
So the report notes that the current «pause» in new global
average temperature records since 1998 — a year that saw the second strongest El Nino on record and shattered
warming records — does not reflect the long - term
trend and may be explained by the oceans absorbing the majority of the extra heat trapped by greenhouse gases as well as the cooling contributions of volcanic eruptions.
The findings show a slight but notable increase in that
average temperature, putting a dent in the idea that global
warming has slowed over the past 15 years, a
trend highlighted in the most recent Intergovernmental Panel on Climate Change report.
Time series of temperature anomaly for all waters
warmer than 14 °C show large reductions in interannual to inter-decadal variability and a more spatially uniform upper ocean
warming trend (0.12 Wm − 2 on
average) than previous results.
While this does not mean that each winter will be
warmer than the one before, the overall
trend indicates that winters have been getting
warmer, on
average, over the last 45 years, and will likely continue to do so.
(1) The
warm sea surface temperatures are not just some short - term anomaly but are part of a long - term observed
warming trend, in which ocean temperatures off the US east coast are
warming faster than global
average temperatures.
Although differing somewhat spatially and seasonally, the
warming trend is seen across all temperature variables, including annual
average, maximum, and minimum temperatures.
While some places were cooler this year than in recent summers, they may have still been above
average over the entire period of record, as
warming trends in
In a long - term
trend that demonstrates the effects of a
warming climate, daily record - high temperatures have recently been outpacing daily record lows by an
average of 2 - to - 1, and this imbalance is expected to grow as the climate continues to
warm.
We assess the heat content change from both of the long time series (0 to 700 m layer and the 1961 to 2003 period) to be 8.11 ± 0.74 × 1022 J, corresponding to an
average warming of 0.1 °C or 0.14 ± 0.04 W m — 2, and conclude that the available heat content estimates from 1961 to 2003 show a significant increasing
trend in ocean heat content.
Even though these are the same areas that tend to have above
average temperatures during El Niño winters, this pattern is also consistent with the long - term
trend we are seeing with global
warming.
The point at which a
trend becomes clear within the
average temperature data for a given region — known as the «time of emergence» — depends on when the source of the
warming begins, how fast it happens and the amount of background «noise» obscuring the signal.
«Despite colder than
average temperatures in any one part of the world, temperatures over the planet as a whole continue the rapid
warming trend we've seen over the last 40 years,» said Gavin Schmidt, director of NASA's Goddard Institute for Space Studies in New York City, at the press conference.
In a long - term
trend that demonstrates the effects of a
warming climate, daily record - high temperatures have recently been outpacing daily record - lows by an
average of 2 - to - 1, and this imbalance is expected to grow as the climate continues to
warm.
The
warming trends in looking at numerous 100 year temperature plots from northern and high elevation climate stations... i.e.
warming trends in annual mean and minimum temperature
averages, winter monthly means and minimums and especially winter minimum temperatures and dewpoints... indicate climate
warming that is being driven by the accumulation of greenhouse gases in the atmosphere — no visible effects from other things like changes in solar radiation or the levels of cosmic rays.
Second, since
warming estimates vary as a function of the GMST data products chosen (Table 2), we propose to estimate
trends on the annual
averages of all five data products.
* However, the same panel then concluded that «the
warming trend in global - mean surface temperature observations during the past 20 years is undoubtedly real and is substantially greater than the
average rate of
warming during the twentieth century.
You can also see in this graph that the
warming trend in the global data for the low troposphere, if we consider the whole set of data, i.e. from the
average between 1980 - 1982 till now, with now meaning the
average of the last three years, the
warming trend is, AT MOST, 0.115 ºC / decade (0.3 ºC in 26 years), but the graph is going down recently, so it should be even less.
Global
warming does not mean no winter, it means winter start later, summer hotter, as Gary Peters said «The global
average surface temperature has risen between 0.6 °C and 0.7 °C since the start of the twentieth century, and the rate of increase since 1976 has been approximately three times faster than the century - scale
trend.»
Winter month
average daily minimum temperature show the strongest
warming trends.
A situation which you describe in the paper (see Figures 3a, 3b, first full paragraph of page 461, that the reconstructed
trends for the Peninsula are less than the global
average and yet you describe is as one of the most rapidly
warming places on earth, that your Figure 4e has spatial differences compared with Supplemental Figure 1c and 1d or the image you linked to in comment 18), and which renders that spatial detail of the cover image difficult to interpret.
The study, described in an article today in The Times, finds that poorly understood variations in water vapor concentrations in the stratosphere were probably responsible for a substantial wedge of the powerful
warming trend in the 1990s and a substantial portion of «the flattening of global
average temperatures since 2000 ″ (to anyone who hates talk of plateaus and the like, those are the authors» words, not mine).
These earlier years, mainly El Nino years,
average 11.5 years earlier than the projected recent hottest four, perhaps suggesting a rough calculation of the recent rate of AGW of at +0.16 ºC / decade, this of course the
warming trend of peak years through the so - called «hiatus» years and being «peak years», it is a rate which assumes cooler years will be coming along soon.
Mr. Chamie notes that the relatively enormous thirst for energy, food and other resources from Americans, when compared with that of the
average world citizen, gives outsize importance to issues like global
warming and to American
trends.
«We show that the climate over the 21st century can and likely will produce periods of a decade or two where the globally
averaged surface air temperature shows no
trend or even slight cooling in the presence of longer - term
warming,» the paper says, adding that, «It is easy to «cherry pick» a period to reinforce a point of view.»
Three of the four global
average temperatures indeed are decreasing in their
trends (although the actual global mean temperatures are still
warmer than the previous decades).
Many scientists note that 1998 was an exceptionally hot year even by modern standards, and so any
average rise using it as a starting point would downplay the longer - term
warming trend.
But, he also says: «teams offering projections say ice extent will remain well below the
average for the last quarter century and a downward
trend in summer ice around the North Pole has not abated,» and we readers are then linked to his October, 2007 article and an August, 2007 image of a «
warmed over» Artic.
Going back to the atmosphere, there must be methods devised in calculating the total heat in the system planet wide, that is the key, I see some efforts in finding Upper Air
trends, that is better, but again flawed, the Upper atmosphere constantly changes tenperatures throughout a vertical profile hour by hour, taking an
average at 700 mb, may miss a strong cooling just below, or
warming above.
In the North Atlantic, the measured values differ markedly from the
average global
warming: the subpolar Atlantic (an area about half the size of the USA, south of Greenland) has hardly
warmed up and in some cases even cooled down, contrary to the global
warming trend.
If you were to read the analysis of the Bouy data you rely on so much you would find that when the inaccuracies are taken out and the differing measurements are corrected and
averaged, there is a clear
warming trend.
If you do the same for 31 year
averages, 32 year
averages, 33 year
averages, etc., on on through at least 70 year
averages, you continue to find an indisputable
trend of climate
warming — even if you dismiss the land data as flawed because of the use of daily extremes rather than a more robust indication of the daily mean.
Schneider et al (2010), which shows a 0.1 C per decade
trend averaged over all of Antarctica, with
warming strongest in the pensinsular, and second strongest in the West Anarctic spring.
There is no spurious
warming due to the chosen practice, «As expected, the global
averaged SSTA
trends between 1901 and 2012 (refer to Table 2) are the same whether buoy SSTs are adjusted to ship SSTs or the reverse.»
While sea ice in the Arctic grows and shrinks with the seasons, there is an overall declining
trend, as north pole has
warmed roughly twice as fast as the global
average.
bozzza - The differences in the Arctic are perhaps 1/4 the ocean thermal mass as global ocean
averages, small overall size (the smallest ocean), being almost surrounded by land (which
warms faster), more limited liquid interchanges due to bottlenecking than the Antarctic, and very importantly considerable susceptibility to positive albedo feedbacks; as less summer ice is present given current
trends, solar energy absorbed by the Arctic ocean goes up very rapidly.
My value of — 0,32 K may be
warmer than your -0,37 K, because I use the
trend values in 2008 to get the number, not an
average value?
We'll also be presenting the
warming and cooling rates (the
trends) on a zonal means (latitude
average) basis.