Sunsettommy
Diamond Member
- Mar 19, 2018
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I also quoted this the other day and you missed it lets see if you are with the IPCC about Climate Emergency:
"Let me begin with the fact that the IPCC itself doesn’t think that there is a “climate crisis” or a “climate emergency”. In the IPCC AR6 WG1, the single mention of a “climate emergency” is a far-too-gentle chiding of the media for using the term, viz:
LINK
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Here are many new ones for you to pass out on:
and,
"And here’s a quote from the Intergovernmental Panel on Climate Change (IPCC):
and,
"This should not surprise anyone—the intractability of climate predictions has long been recognized even by the IPCC, viz:
and,
DIRECT QUOTES FROM VARIOUS IPCC REPORTS
The impacts of changes in flood characteristics are also highly dependent on how climate changes in the future, and as noted in Section 3.5.2, there is low confidence in projected changes in flood magnitude or frequency.
There are inconsistent patterns of change in heavy precipitation in Africa and partial lack of data; hence there is low confidence in observed precipitation trends
There is medium confidence in projected poleward shifts of mid-latitude storm tracks but low confidence in detailed regional projections
There is thus low confidence in the level at which global warming could lead to very high risks associated with extreme weather events in the context of this report.
Low confidence in an observed global-scale trend in drought or dryness (lack of rainfall) since the 1950s, due to lack of direct observations, methodological uncertainties and choice and geographical inconsistencies in the trends
Low confidence in attributing changes in drought over global land areas since the mid20th century to human influence owing to observational uncertainties and difficulties in distinguishing decadal-scale variability in drought from long-term trends.
The IPCC AR5 (2013) stressed low confidence in a global-scale observed trend in drought, owing to lack of direct observations, dependencies of inferred trends on the index choice, as well as difficulties in distinguishing long-term climate change from decadal-scale drought variability
Tropical cyclones are projected to decrease in frequency but with an increase in the number of very intense cyclones (limited evidence, low confidence).
There is thus low confidence in the level at which global warming could lead to very high risks associated with extreme weather events in the context of this report.
Observed global changes in the water cycle, including precipitation, are more uncertain than observed changes in temperature (Hartmann et al., 2013; Stocker et al., 2013). There is high confidence that mean precipitation over the mid-latitude land areas of the Northern Hemisphere has increased since 1951 (Hartmann et al., 2013). For other latitudinal zones, area-averaged long-term positive or negative trends have low confidence because of poor data quality, incomplete data or disagreement amongst available estimates (Hartmann et al., 2013). There is, in particular, low confidence regarding observed trends in precipitation in monsoon regions, according to the SREX report (Seneviratne et al., 2012) and AR5 (Hartmann et al., 2013), as well as more recent publications (Singh et al., 2014; Taylor et al., 2017; Bichet and Diedhiou, 2018; see Supplementary Material 3.SM.2).
Consequently, the current assessment is that there is low confidence regarding changes in monsoons at these lower global warming levels, as well as regarding differences in monsoon responses at 1.5°C versus 2°C.
The IPCC AR5 assessed that there was low confidence in the sign of drought trends since 1950 at the global scale,
AR5 assessed that there was low confidence in the attribution of global changes in droughts and did not provide assessments for the attribution of regional changes in droughts (Bindoff et al., 2013a)
Such contradictions, in combination with the fact that the almost four-decade-long period of remotely sensed observations remains relatively short to distinguish anthropogenically induced trends from decadal and multi-decadal variability, implies that there is only low confidence regarding changes in global tropical cyclone numbers under global warming over the last four decades.
Likewise, CMIP5 model simulations of the historical period have not produced anthropogenically induced trends in very intense tropical cyclones (Bender et al., 2010; Knutson et al., 2010, 2013; Camargo, 2013; Christensen et al., 2013), consistent with the findings of Klotzbach and Landsea (2015). There is consequently low confidence in the conclusion that the number of very intense cyclones is increasing globally.
AR5 assessed that under high greenhouse gas forcing (3°C or 4°C of global warming) there is low confidence in projections of poleward shifts of the Northern Hemisphere storm tracks, while there is high confidence that there would be a small poleward shift of the Southern Hemisphere storm tracks (Stocker et al., 2013). In the context of this report, the assessment is that there is limited evidence and low confidence in whether any projected signal for higher levels of warming would be clearly manifested under 2°C of global warming.
Collins et al. (2013) assessed low confidence in Antarctic sea ice projections because of the wide range of model projections and an inability of almost all models to reproduce observations such as the seasonal cycle, interannual variability and the long-term slow increase.
There was low confidence due to limited evidence, however, that anthropogenic climate change has affected the frequency and magnitude of floods. WGII AR5 also concluded that there is no evidence that surface water and groundwater drought frequency has changed over the last few decades, although impacts of drought have increased mostly owing to increased water demand (Jiménez Cisneros et al., 2014)
Reduced ocean upwelling has implications for millions of people and industries that depend on fisheries for food and livelihoods (Bakun et al., 2015; FAO, 2016; Kämpf and Chapman, 2016), although there is low confidence in the projection of the size of the consequences at 1.5°C
Evidence of a slowdown of AMOC has increased since AR5 (Smeed et al., 2014; Rahmstorf et al., 2015a, b; Kelly et al., 2016), yet a strong causal connection to climate change is missing (low confidence)
The magnitude of global sea level rise that could occur over the next two centuries under 1.5°C–2°C of global warming is estimated to be in the order of several tenths of a metre according to most studies (low confidence)
That is, although restraining the global temperature increase to 2°C is projected to reduce crop losses under climate change relative to higher levels of warming, the associated mitigation costs may increase the risk of hunger in low-income countries (low confidence)
Overall, no statistically significant changes in GDP are projected to occur over most of the developed world under 1.5°C of global warming in comparison to present-day conditions, but under 2°C of global warming impacts on GDP are projected to be generally negative (low confidence)
Moreover, daily rainfall intensity and runoff is expected to increase (low confidence) towards 2°C and higher levels of global warming
A collapse in permafrost may occur (low confidence); a drastic biome shift from tundra to boreal forest is possible (low confidence)
The number of investigations into how the tree fraction may respond in the Arctic to different degrees of global warming is limited, and studies generally indicate that substantial increases will likely occur gradually (e.g., Lenton et al., 2008). Abrupt changes are only plausible at levels of warming significantly higher than 2°C (low confidence) and would occur in conjunction with a collapse in permafrost
A single model projection (Drijfhout et al., 2015) suggested that higher temperatures may induce a smaller ice fraction in soils in the tundra, leading to more rapidly warming soils and a positive feedback mechanism that results in permafrost collapse (low confidence).
Given that scenarios of 1.5°C or 2°C of global warming would include a substantially smaller radiative forcing than those assessed in the study by Jiang and Tian (2013), there is low confidence regarding changes in monsoons at these low global warming levels, as well as regarding the differences between responses at 1.5°C versus 2°C of warming.
A tipping point for significant dieback of the boreal forests is thought to exist, where increased tree mortality would result in the creation of large regions of open woodlands and grasslands, which would favour further regional warming and increased fire frequencies, thus inducing a powerful positive feedback mechanism (Lenton et al., 2008; Lenton, 2012). This tipping point has been estimated to exist between 3°C and 4°C of global warming (low confidence) (Lucht et al., 2006; Kriegler et al., 2009), but given the complexities of the various forcing mechanisms and feedback processes involved, this is thought to be an uncertain estimate.
These changes may be classified as incremental rather than representing a tipping point. Large-scale reductions in maize crop yield, including the potential collapse of this crop in some regions, may exist under 3°C or more of global warming (low confidence)
Under 3°C of global warming, significant reductions in the areas suitable for livestock production could occur (low confidence)
Tropical cyclones are projected to decrease in frequency but with an increase in the number of very intense cyclones (limited evidence, low confidence).
Climate models now include more cloud and aerosol processes, and their interactions, than at the time of the AR4, but there remains low confidence in the representation and quantification of these processes in models.
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You climate scaremongering gooks ignore this all the time,
"Next, here is the radical change in downwelling radiation at the surface from the increase in CO2 that is supposed to be driving the “CLIMATE EMERGENCY!!!” What I’ve shown is the change that in theory would have occurred from the changes in CO2 from 1750 to the present, and the change that in theory will occur in the future when CO2 increases from its present value to twice the 1750 value. This is using the generally accepted (although not rigorously derived) claim that the downwelling radiation change from a doubling of CO2 is 3.5 watts per square metre (W/m2). The purpose is to show how small these CO2-caused changes are compared to total downwelling radiation.
The changes in downwelling radiation from the increase in CO2 are trivially small, lost in the noise …"
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