This experiment showed that the projections of climate models are consistent with recorded temperature
trends over recent decades only if human impacts are included.
Scientists have high confidence about global temperature
trends over recent decades because those observations are based on a massive amount of data.
As noted above, most earlier hindcasts of 20th century climate as well as current IPCC AR4 runs [Miller et al., 2006; Knutson et al., 2006] do not reproduce the observed
trends over recent decades in the AO component of the circulation, and thus do not capture the intensification of warming trends that has been observed over Northern Europe and Asia.
The «selling point» of the paper is that with the updates to data and corrections,
the trend over the recent decade or so is now significantly positive.
Potentially more worrying, the 2015/2016 floods appear to be part of
a trend over recent decades for more frequent extreme winter rainfall events.
That the climate models are remarkably close to the observed temperature
trend over the recent decade, taking into consideration all relevant factors, is an explicit demonstration that we can get this temporary surface temperature slowdown even when the Earth's climate sensitivity is around 3 °C per doubling of CO2.
As Gavin Schmidt, director of NASA's Goddard Institute for Space Studies, put it in a post on the Real Climate blog: «The «selling point» of the paper is that with the updates to data and corrections,
the trend over the recent decade or so is now significantly positive.
Not exact matches
Growth of non-farm GDP
over the latest four quarters for which we have data was just
over 4 per cent; domestic demand, while slowing a little from its most
recent peak, expanded by 5 1/2 per cent
over that period; employment growth
over the past year has been around
trend, though lower in
recent months, and the unemployment rate has remained close to the lower end of the range in which it has fluctuated
over the past two
decades.
But
recent trends do point toward a changing wind in culture — a sense that sex and nudity and female actors in particular might be deserving of a little more respect than they've been getting
over the past
decade.
To put
recent trends in even sharper relief, 205 abortion restrictions were enacted
over the past three years (2011 — 2013), but just 189 were enacted during the entire previous
decade (2001 — 2010).
Dr Ghassem Asrar, Director of JGCRI, a co-author of study, said: «Among global regions, there was notable variability in
trends in estimated emissions
over recent decades.
«Whilst they likely capture an element of natural variability, the strong anthropogenic
trends observed
over recent decades likely masks the true natural rhythms of the climate system.
There have certainly been some large El Nino events
over the past couple
decades, and this leverages any linear
trend estimates of the long - term behavior (such as those shown in the
recent Vecchi et al paper, which we'll be talking about more in a follow - up post to this).
Total hurricane frequency is projected to decline, and
over recent decades, there is no clear
trend, but only year to year variations.
A: Climate changes observed
over recent decades are inconsistent with
trends caused by natural forces but are totally consistent with the increase in human - induced heat - trapping gases.
A colleague informed him of a startling
trend: liver cancer was plaguing affluent Filipinos at a much higher rate than their less - wealthy counterparts — a phenomenon that, despite a slew of other lifestyle differences, Campbell believed was linked to their higher intake of animal protein.1 Bolstering his suspicions, Campbell also learned of a
recent study from India showing that a high protein intake spurred liver cancer in rats, while a low protein intake seemed to prevent it.2 Intrigued by this gem of little - known research, Campbell decided to investigate the role of nutrition in cancer growth himself — an endeavor that ended up lasting several
decades and producing
over one hundred publications (none of which pertained to Fight Club).3
Following
recent demand - driven reforms, some universities are admitting larger numbers of teacher education students with increasingly low Year 12 performances — a
trend that may continue as the number of teachers required to staff our schools grows
over the next
decade.
Unlike income achievement gaps, the racial academic achievement gaps have declined significantly
over the past four
decades, the researchers said, so the
recent narrowing of the racial readiness gap among kindergarteners is merely a continuation of the
trend.
Travel Incorporated has offered group air services for
over a
decade under the TI Groups umbrella, servicing corporate clients and incentive houses nationwide; however the
recent surge in industry demand for high - touch services, together with corporate
trending towards Strategic Meetings Management initiatives has created a void in both the services and expertise now available industry - wide, which is the underlying principle behind launching GTP as a separate entity.
Finally, to show that cosmic rays were actually responsible for some part of the
recent warming you would need to show that there was actually a decreasing
trend in cosmic rays
over recent decades — which is tricky, because there hasn't been (see the figure)(Missing step # 5).
If one plots the records from GISS, HADCru, RSS and UAH; GISS is the outlier, and three of the four primary global temperature measuring systems show a decrease
over the most
recent six years and a downward
trend over the past
decade; not that this establishes a significant
trend yet.
There have certainly been some large El Nino events
over the past couple
decades, and this leverages any linear
trend estimates of the long - term behavior (such as those shown in the
recent Vecchi et al paper, which we'll be talking about more in a follow - up post to this).
We also hypothesize that shoaling of the thermocline
over the EEIO, corresponding to a subsurface cooling
trend (Alory et al. 2007), can make this region more susceptible to the wind — thermocline feedback and leads to frequent occurrences of positive events in
recent decades.
Another equally important challenge is the fact that there are pronounced ~ 11 - year variations in the CRF, but the presence of ~ 11 - year variations in the global mean temperature are much less pronounced than the
trend over the 3 — 4 most
recent decades.
No
trend in 30 years is the summary statement — that 2001 paper shows no
trend over 1980 - 2000; other work cited in the intermediate article shows no
trend during the most
recent decade.
For example the increasing
trend in the coherent NHSM decadal precipitation shown in the paper (Figure S3B: the spatial pattern and associated principal component time series of the EOF) in fact suggest a weakening
over recent decades in much of India and East Asia.
Of course, the warming linear
trend over that most
recent 1999 - 2014 span (including NASA's newest hottest year /
decade ever) is an even bigger LOL - a
trend that equates to +0.26 °C increase by 2100.
Recent and very precise satellite measurements taken
over the past few
decades have confirmed this
trend.
The forests of the eastern United States (including the Midwest) have been accumulating large quantities of carbon
over the past century, 26 but evidence shows this
trend is slowing in
recent decades.
The
trend in the NAM helps explain the spatial structure of
recent trends in NH climate and several ecosystems
over the past few
decades.
Your «standstill» here is just the fact that one can't statistically detect a warming
trend in the mentioned temperature anomaly
over the short time period of the
recent decade.
A flurry of
recent research strongly suggests that
recent observations like these are indeed linked to California's long - term warming
trend — and that snowpack losses are expected to accelerate further
over the next few
decades.
These
trend figures also match those from a
recent comprehensive surface station based study of the Arctic which gives 0.364 degrees C /
decade from 60 - 90N
over this same period (Bekryaev 2010).
A: Climate changes observed
over recent decades are inconsistent with
trends caused by natural forces but are totally consistent with the increase in human - induced heat - trapping gases.
Such models also indicate that warming would initially cause the Antarctic ice sheet as a whole to gain mass owing to an increased accumulation of snowfall (*; some
recent studies find no significant continent - wide
trends in accumulation
over the past several
decades; Lemke et al., 2007 Section 4.6.3.1).
Changes in CO2 emissions attributed to Kaya Identity factors from 2015 to 2016 compared with the
trend from the prior
decade: This figure gives context to the most
recent year ‐ to ‐ year change by comparing it to the average change for key parameters
over the previous
decade.
Chris This means that the data does show, with confidence, a short term
trend which is less than the longer term
trend we've seen
over recent decades.
More broadly, the panel examined other
recent research comparing the pronounced warming
trend over the last several
decades with temperature shifts
over the last 2,000 years.
These
trends in extreme weather events are accompanied by longer - term changes as well, including surface and ocean temperature increase
over recent decades, snow and ice cover decrease and sea level rise.
I have to conclude by suggesting that if the reported temperature record itself is something that you believe may be very different from the true
trend of anomalies
over the many
decades of the past century — particularly the more
recent decades — then you are probably grasping a slim reed in hoping to question mainstream conclusions.
Higher spring and summer temperatures, along with an earlier spring melt, are also the primary factors driving the increasing frequency of large wildfires and lengthening the fire season in the western U.S.
over recent decades.13 The record - breaking fires this year in the Southwest and Rocky Mountain Region are consistent with these
trends.
In fact, in the most
recent few
decades, the rural sites have become slightly warmer than the full data set, and show a
trend of -0.19 + / - 0.19 °C per century
over the 1950 - 2010 time period, roughly consistent with the
trends reported in the first method.
Mainstream climate scientists tend to suggest that it has,
over recent decades, reduced rather than increased the observed
trend.
The resulting
trends over recent periods in °C /
decade are given in the following table:
Over the most recent 17 - year period, the BEST trend is 0.36 °C per decade *, clearly showing the anthropogenic warming trend over that per
Over the most
recent 17 - year period, the BEST
trend is 0.36 °C per
decade *, clearly showing the anthropogenic warming
trend over that per
over that period.
Weather fluctuates, and as a consequence itâ $ ™ s easy enough to point to an unusually warm year in the
recent past, note that itâ $ ™ s cooler now and claim, â $ œSee, the planet is getting cooler, not warmer!â $ But if you look at the evidence the right way Ââ $» taking averages
over periods long enough to smooth out the fluctuations â $» the upward
trend is unmistakable: each successive
decade since the 1970s has been warmer than the one before.
if no individual tide gauge records show a
recent surge (and only a tiny fraction of long running ones show any
trend change at all in
recent decades), then claims that sea levels are surging are simply not tenable, for if GLOBAL sea levels are rising you would by logic alone expect that this would show up in actual single sites all
over the globe.
You need a lesson in street smart logic: if no individual tide gauge records show a
recent surge (and only a tiny fraction of long running ones show any
trend change at all in
recent decades), then claims that sea levels are surging are simply not tenable, for if GLOBAL sea levels are rising you would by logic alone expect that this would show up in actual single sites all
over the globe.
«The land — sea warming ratio in the ECHAM — HadISST holds also for the warming
trend over the most
recent decades, despite the fact that no anthropogenic radiative forcings are included in the simulations.
This mirrors the significant rise in global temperatures detected
over the past 30 years, supporting the conclusion that there is a global
trend toward enhanced glacier frontal recession in
recent decades and providing support for the assertion that glacier recession can be attributed to
recent warming.»