Not exact matches
Growing scarcity
In addition to a growing scarcity of
natural resources such as land, water and biodiversity «global agriculture will have to cope
with the effects of
climate change, notably higher temperatures, greater rainfall
variability and more frequent extreme weather events such as floods and droughts,» Diouf warned.
Such offices shall engage
in cooperative research, development, and demonstration projects
with the academic community, State
Climate Offices, Regional Climate Offices, and other users and stakeholders on climate products, technologies, models, and other tools to improve understanding and forecasting of regional and local climate variability and change and the effects on economic activities, natural resources, and water availability, and other effects on communities, to facilitate development of regional and local adaptation plans to respond to climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Com
Climate Offices, Regional
Climate Offices, and other users and stakeholders on climate products, technologies, models, and other tools to improve understanding and forecasting of regional and local climate variability and change and the effects on economic activities, natural resources, and water availability, and other effects on communities, to facilitate development of regional and local adaptation plans to respond to climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Com
Climate Offices, and other users and stakeholders on
climate products, technologies, models, and other tools to improve understanding and forecasting of regional and local climate variability and change and the effects on economic activities, natural resources, and water availability, and other effects on communities, to facilitate development of regional and local adaptation plans to respond to climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Com
climate products, technologies, models, and other tools to improve understanding and forecasting of regional and local
climate variability and change and the effects on economic activities, natural resources, and water availability, and other effects on communities, to facilitate development of regional and local adaptation plans to respond to climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Com
climate variability and change and the effects on economic activities,
natural resources, and water availability, and other effects on communities, to facilitate development of regional and local adaptation plans to respond to
climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Com
climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Committee.
Ultimately,
in forests not otherwise limited by energy or nutrients
variability in moisture availability
with natural and
climate oscillations may drive establishment success between years (League and Veblen 2006),
with indirect disturbance effects (e.g., fires, landslides, insect outbreaks, and pathogen attacks) greatly affecting long - term recruitment success (Clark et al. 2016).
Results of both regional
climate model simulations and observational analyses suggest that much of the observed rainfall increase — as well as the decrease
in temperature and increase
in humidity — is attributable to agricultural intensification
in the central United States,
with natural variability and GHG emissions playing secondary roles.
The
climate information
in particular is tricky to work
with in such snapshot comparisons because it can fall prey to the ups and downs of
natural year - to - year
variability, Doney said.
«It's important to determine where we believe that some of the recent trends
in circulation could potentially be linked
with climate change, rather than just
natural variability,» Ted Shepherd, an atmospheric scientist at the University of Reading
in the U.K., said
in an email.
«The reconstruction of past
climate reveals that recent warming
in the Arctic and
in the Northern Hemisphere is highly inconsistent
with natural climate variability over the last 2000 years.»
The knowledge gap may just have narrowed, however,
with the publication of a new study
in Nature (one of two we're reporting on this week, as it happens) that appears to move the explanation for one type of
climate variability from the
natural to the human camp.
Observed changes
in ocean heat content have now been shown to be inconsistent
with simulated
natural climate variability, but consistent
with a combination of
natural and anthropogenic influences both on a global scale, and
in individual ocean basins.
Natural climate variability of the Arctic atmosphere, the impact of Greenland and PBL stability changes K. Dethloff *, A. Rinke *, W. Dorn *, D. Handorf *, J. H. Christensen ** * AWI Potsdam, ** DMI Copenhagen Unforced and forced long - term model integrations from 500 to 1000 years
with global coupled atmosphere - ocean - sea - ice models have been analysed
in order to find out whether the different models are able to simulate the North Atlantic Oscillation (NAO) similar to the real atmosphere.
«There is high confidence that the El Niño - Southern Oscillation (ENSO) will remain the dominant mode of
natural climate variability in the 21st century
with global influences
in the 21st century, and that regional rainfall
variability it induces likely intensifies.
The insufficient observational coverage has also been noted by the IPCC AR4 and by Gillett et al. (Nature Geoscience, 2008), who argue that the observed warming
in the Arctic and Antarctic are not consistent
with internal
climate variability and
natural forcings alone, but are directly attributable to increased GHG levels.
If we have some time to prepare, the combination of lowering all the discussed emissions, utilizing current technology to implement alternative energy sources, and engineering new twists on said technology to both continue lowering emissions and adapting to global
climate changes as well, we may be able to guide our response sets to outside, artificial selective pressures
in conjunction
with natural ones;
natural, internal
variability and external forcings / feedbacks.
Here we use a risk assessment framework to examine the potential impact of El Nino events and
natural variability on rice agriculture
in 2050 under conditions of
climate change,
with a focus on two main rice - producing areas: Java and Bali.
But, on the basis of studies of nonlinear chaotic models
with preferred states or «regimes», it has been argued, that the spatial patterns of the response to anthropogenic forcing may
in fact project principally onto modes of
natural climate variability.
To show,
in a peer - reviewed scientifically defensible way that there is no reason to expect the
climate to warm
in a monotonic type fashion, that there is
natural variability along
with anthropogenic forced warming and we shouldn't expect each year to be warmer than the next or even a run of 10 years always to show warming.
If you can't keep up
with annual - decadal changes
in the TOA radiative imbalance or ocean heat content (because of failure to correctly model changes
in the atmosphere and ocean due to
natural variability), then your
climate model lacks fidelity to the real world system it is tasked to represent.
The implications of our findings are that the modern observations of ocean - driven warming along the western Antarctic Peninsula need to be considered as part of a
natural centennial timescale cycle of
climate variability, and that
in order to understand
climate change along the Antarctic Peninsula, we need to understand the broader
climate connections
with the rest of the planet.
So: The study finds a fingerprint of anthropogenic influences on large scale increase
in precipitation extremes,
with remaining uncertainties — namely that there is still a possibility that the widespread increase
in heavy precipitation could be due to an unusual event of
natural variability.The intensification of extreme rainfall is expected
with warming, and there is a clear physical mechanism for it, but it is never possible to completely separate a signal of external forcing from
climate variability — the separation will always be statistical
in nature.
In your book, you explain your research began
with natural climate variability and you said you believed this was a more important aspect to
climate change than many scientists thought.
Again,
natural variability has been ignored
in order to support a particular point of view,
with climate change advocates leaping on the acceleration to further their cause and the
climate change sceptics now using the slowing down to their own benefit.
In terms of how to deal
with both
natural and human - caused
climate variability and change, we wrote:
For instance, the warming that began
in the early 20th century (1925 - 1944) is consistent
with natural variability of the
climate system (including a generalized lack of significant volcanic activity, which has a cooling effect), solar forcing, and initial forcing from greenhouse gases.
Heck, even if AGW weren't an issue, understanding the range of
climate variation (that is temperature, precipitation, cloud cover, etc) expected from
natural variability is still something that needs quantifying accurately, especially as we zoom towards a 10 - billion world population
with all of the major agricultural areas concentrated
in small regions of the globe.
A new study suggests that species that have evolved
in regions
with relatively high
natural climate variability may at the same time be more resilient... Continue reading →
The extremes of the 1930's and 1950's are not attributable to greenhouse warming and are associated
with natural climate variability (and
in the case of the dustbowl drought and heat waves, also to land use practices).
Natural variability makes it difficult to invalidate
climate models that make predictions disagree
with observations, such as amplification of warming
in the upper tropical troposphere.
Natural variability from the ensemble of 587 21 - year - long segments of control simulations (
with constant external forcings) from 24 Coupled Model Intercomparison Project phase 3 (CMIP3)
climate models is shown
in black and gray.
It would certainly help
in terms of
natural climate variability, but I don't think it is going to help
with climate sensitivity.
Paleo evidence have indeed shown quite strong spikes
in temperature anomolies which gets back to the most important point of your paper
with Judith: the extent of
natural internal
variability needs to be disentangled from anthropogenic and other forcings before we can make any conclusions about the future course of
climate.
Far from changing one's conception of
natural mutidecadal
variability, this paper succeeds only
in re-inforcing the reputation of «
climate science» as a speculative handwaving» exercise, replete
with ill - conceived notions of «feedbacks.
Those changes are not easy to measure or reproduce
with climate models, and some researchers think
natural variability or changes
in the tropics are more important drivers of weather extremes
in the mid-latitudes.
(Note: the biggest issue is
climate sensitivity,
with a secondary issue being the magnitude of modes of
natural internal
variability on multi-decadal time scales, and tertiary issues associated model inadequacies
in dealing
with aerosol - cloud processes and solar indirect effects.)
Contrary to another claim made by Betts, we are conversant
with that research and have recently contributed to it by showing that
climate models do accommodate recent temperature trends when the phasing of
natural internal
variability is taken into account — as it must be
in comparing a projection to a single outcome.
First, the 20th century warming is only «consistent
with natural variability» if one imagines sources of
variability that have not emerged
in the
climate record over the course of millions of years.
IPCC relied on
climate models (CMIP5), the hypotheses under test if you will, to exclude
natural variability: «Observed Global Mean Surface Temperature anomalies... lie well outside the range of Global Mean Surface Temperature anomalies
in CMIP5 simulations
with natural forcing only, but are consistent
with the ensemble of CMIP5 simulations including both anthropogenic and
natural forcing...» (Ref.: Working Group I contribution to fifth assessment report by IPCC.
If you selectively read only the literature about the role of
natural variability in climate, then your personal knowledge will lead to a flag
with a large green portion (which seems to be where most of the commenters at WUWT are).
There are much better arguments on other items where (C) AGW is on thin ice:
climate models which fail on a lot of items like cloud cover, overestimate the influence of aerosols, can't cope
with natural variability and therefore fail
in their temperature forecasts.
Such offices shall engage
in cooperative research, development, and demonstration projects
with the academic community, State
Climate Offices, Regional Climate Offices, and other users and stakeholders on climate products, technologies, models, and other tools to improve understanding and forecasting of regional and local climate variability and change and the effects on economic activities, natural resources, and water availability, and other effects on communities, to facilitate development of regional and local adaptation plans to respond to climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Com
Climate Offices, Regional
Climate Offices, and other users and stakeholders on climate products, technologies, models, and other tools to improve understanding and forecasting of regional and local climate variability and change and the effects on economic activities, natural resources, and water availability, and other effects on communities, to facilitate development of regional and local adaptation plans to respond to climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Com
Climate Offices, and other users and stakeholders on
climate products, technologies, models, and other tools to improve understanding and forecasting of regional and local climate variability and change and the effects on economic activities, natural resources, and water availability, and other effects on communities, to facilitate development of regional and local adaptation plans to respond to climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Com
climate products, technologies, models, and other tools to improve understanding and forecasting of regional and local
climate variability and change and the effects on economic activities, natural resources, and water availability, and other effects on communities, to facilitate development of regional and local adaptation plans to respond to climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Com
climate variability and change and the effects on economic activities,
natural resources, and water availability, and other effects on communities, to facilitate development of regional and local adaptation plans to respond to
climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Com
climate variability and change, and any other needed research identified by the Under Secretary or the Advisory Committee.
Roger could reply again by stating that models that don't show skill
in projecting changing statistics can not be used for this reasoning by simulation, but I remain to disgree
with him: the skill of
climate models to project changing
climate statistics at decadal time scales can formally not be established due to large role of
natural variability, but is also not always required for generating useful information that enters the imagination process.
You have not cited a third possibility (out of the infinite range of possibilities), no
climate change associated
with CO2 (due to, for example, cloud cover providing negative feedback),
with current increase due to
natural variability; or how about possibility four, that increase
in CO2 concentrations are caused by the temperature rise, which is
in turn caused by (for example) increased solar activity resulting
in increased biomass activity etc. etc..
Even assuming the models are a perfect characterisation of the forced response and
natural variability of the
climate system (
in statistical terms), his calculation will (
with high probability) find that the obs are not consistent
with the mean.
• the contribution of
natural climate variability to decade - to - decade
climate changes, including changes
in the atmosphere's vertical structure associated
with natural variability;
Taking inspiration from the Three Body Gravitational Problem (http://www.upscale.utoronto.ca/PVB/Harrison/Flash/Chaos/ThreeBody/ThreeBody.html),
with anthropogenic influences as Sun 1 and
natural variability as Sun 2, the
climate (planet) does not promise forever to orbit
in familiar paths.
As I said, when comparing
with observations over the short period being considered here, it makes more sense to compare
with models that include
natural internal
variability (i.e.: GCMs — as
in the final version) than against models that do not include this and only include externally - forced changes (ie: Simple
Climate Models, SCMs, — as
in the SOD version).
It doesn't mean that there can't be any
natural variability that appears as wobbles
in the temperature record (or
in other
climate variables), masking the multi-decadal temperature trend over a time scale shorter than 20 years
with the effect that the longer term trend is not statistically detectable
in the time series, if one chooses the time period only short enough.
Jan Perlwitz says:» It doesn't mean that there can't be any
natural variability that appears as wobbles
in the temperature record (or
in other
climate variables), masking the multi-decadal temperature trend over a time scale shorter than 20 years
with the effect that the longer term trend is not statistically detectable
in the time series, if one chooses the time period only short enough.»
Firstly, even
with man - made global warming taken into account, because of the short - term noise due to the internal
variability in the
climate system,
climate models predict that there will be decades where
natural cycles dampen the man - made warming trend.
The distribution, cyclical pattern, rate, and extent of recent global warming are [fully / mostly / partially / not] consistent
with natural variability in Earth's
climate.
The advantage of recognising a reversed sign for the solar effect high up
in the atmosphere is that it enables a scenario whereby the bottom up effects of ocean cycles and the top down effects of solar
variability can be seen to be engaged
in a complex ever changing dance
with the primary
climate response being changes
in the tropospheric air circulation systems to give us the observed
natural climate variability via cyclical latitudinal shifts
in all the air circulation systems and notably the jet streams.