Showing posts with label extreme weather events. Show all posts
Showing posts with label extreme weather events. Show all posts

Wednesday, January 30, 2019

A Revision of Future Climate Change Trends

By Andrew Glikson


As the Earth continues to heat, paleoclimate evidence suggests transient reversals will result in accentuating the temperature polarities, leading to increase in the intensity and frequency of extreme weather events.

Pleistocene paleoclimate records indicate interglacial temperature peaks are consistently succeeded by transient stadial freeze events, such as the Younger Dryas and the 8.5 kyr-old Laurentide ice melt, attributed to cold ice melt water flow from the polar ice sheets into the North Atlantic Ocean. The paleoclimate evidence raises questions regarding the mostly linear to curved future climate model trajectories proposed for the 21ᵗʰ century and beyond, not marked by tipping points. However, early stages of a stadial event are manifest by a weakening of the North Atlantic overturning circulation and the build-up of a large pool of cold water south and east of Greenland and along the fringes of Western Antarctica. Comparisons with climates of the early Holocene Warm Period and the Eemian interglacial when global temperatures were about +1°C higher than late Holocene levels. The probability of a future stadial event bears major implications for modern and future climate change trends, including transient cooling of continental regions fringing the Atlantic Ocean, an increase in temperature polarities between polar and tropical zones across the globe, and thereby an increase in storminess, which need to be taken into account in planning global warming adaptation efforts.


Reports of the International Panel of Climate Change (IPCC)⁽¹⁾, based on thousands of peer reviewed science papers and reports, offer a confident documentation of past and present processes in the atmosphere⁽²⁾, including future model projections (Figure 1). When it comes to estimates of future ice melt and sea level change rates, however, these models contain a number of significant departures from observations based on the paleoclimate evidence, from current observations and from likely future projections. This includes departures in terms of climate change feedbacks from land and water, ice melt rates, temperature trajectories, sea level rise rates, methane release rates, the role of fires, and observed onset of transient stadial (freeze) events⁽³⁾. Early stages of stadial event/s are manifest by the build-up of a large pool of cold water in the North Atlantic Ocean south of Greenland and along the fringes of the Antarctic continent (Figure 2).
Figure 1. IPCC AR5: Time series of global annual mean surface air temperature anomalies relative to 1986–2005
from CMIP5 (Coupled Model Inter-comparison Project) concentration-driven experiments.
Projections are shown for each RCP for the multi model mean (solid lines) and the 5–95%
range (±1.64 standard deviation) across the distribution of individual models (shading).⁽⁴⁾
Hansen et al. (2016) (Figure 2) used paleoclimate data and modern observations to estimate the effects of ice melt water from Greenland and Antarctica, showing cold low-density meltwater tend to cap increasingly warm subsurface ocean water, affecting an increase ice shelf melting, accelerating ice sheet mass loss (Figure 3) and slowing of deep water formation (Figure 4). Ice mass loss would raise sea level by several meters in an exponential rather than linear response, with doubling time of ice loss of 10, 20 or 40 years yielding multi-meter sea level rise in about 50, 100 or 200 years.

Linear to curved temperature trends portrayed by the IPCC to the year 2300 (Figure 1) are rare in the Pleistocene paleo-climate record, which abrupt include warming and cooling variations during both glacial (Dansgaard-Oeschger cycles; Ganopolski and Rahmstorf 2001⁽⁵⁾; Camille and Born, 2019⁽⁶⁾) and interglacial (Cortese et al. 2007⁽⁷⁾) periods. Hansen et al.’s (2016) model includes sharp drops in temperature, reflecting stadial freezing events in the Atlantic Ocean and the sub-Antarctic Ocean and their surrounds, reaching -2°C over several decades (Figure 5).
Figure 2. 2055-2060 surface-air temperature to +1.19°C above 1880-1920
(AIB model modified forcing, ice melt to 1 meter) From: Hansen et al. (2016)⁽⁸⁾
Figure 3. Greenland and Antarctic ice mass change. GRACE data are extension of Velicogna et al. (2014)⁽⁹⁾
gravity data. MBM (mass budget method) data are from Rignot et al. (2011)⁽¹⁰⁾. Red curves are gravity
data for Greenland and Antarctica only; small Arctic ice caps and ice shelf melt add to freshwater input.⁽¹¹⁾
Figure 4. (a) AMOC (Sverdrup⁽¹²⁾) at 28°N in simulations (i.e., including freshwater injection of 720 Gt year−1 in 2011
                around Antarctica, increasing with a 10-year doubling time, and half that amount around Greenland).
(b) SST (°C) in the North Atlantic region (44–60°N, 10–50°W).
Temperature and sea level rise relations during the Eemian interglacial⁽¹³⁾ about 115-130 kyr ago, when temperatures were about +1°C or higher than during the late stage of the Holocene, and sea levels were +6 to +9 m higher than at present, offer an analogy for present developments. During the Eemian overall cooling of the North Atlantic Ocean and parts of the West Antarctic fringe ocean due to ice melt led to increased temperature polarities and to storminess⁽¹⁴⁾, underpinning the danger of global temperature rise to +1.5°C. Accelerating ice melt and nonlinear sea level rise would reach several meters over a timescale of 50–150 years (Hansen et al. 2016)

Figure 5. Global surface-air temperature to the year 2300 in the North Atlantic and Southern Oceans,
including stadial freeze events as a function of Greenland and Antarctic ice melt doubling time

Portents of collapse of the Atlantic Meridional Ocean Circulation (AMOC)

The development of large cold water pools south and east of Greenland (Rahmstorf et al. 2015⁽¹⁵⁾) and at the fringe of West Antarctica (Figures 1 and 5) signify early stages in the development of a stadial, consistent with the decline in the Atlantic Meridional Ocean Circulation (AMOC) (Figure 4). These projections differ markedly from linear model trends (Figure 1). IPCC models mainly assume long term ice melt⁽¹⁶⁾, stating “For the 21st century, we expect that surface mass balance changes will dominate the volume response of both ice sheets (Greenland and Antarctica). A key question is whether ice-dynamical mechanisms could operate which would enhance ice discharge sufficiently to have an appreciable additional effect on sea level rise”⁽¹⁷⁾. The IPCC conclusion is difficult to reconcile with studies by Rignot et al. (2011) reporting that in 2006 the Greenland and Antarctic ice sheets experienced a “combined mass loss of 475 ± 158 Gt/yr, equivalent to 1.3 ± 0.4 mm/yr sea level rise”⁽¹⁸⁾. For the Antarctic ice sheet the IEMB team (2017) states the sheet lost 2,720 ± 1,390 billion tonnes of ice between 1992 and 2017, which corresponds to an increase in mean sea level of 7.6 ± 3.9 millimeter⁽¹⁹⁾.

A non-linear climate warming trend, including stadial freeze events, bears significant implications for planning future adaptation efforts, including preparations for transient deep freeze events in parts of Western Europe and eastern North America, for periods lasting several decades (Figure 5) and coastal defenses against enhanced storminess arising from increased temperature contrasts between the cooled regions and warm tropical latitudes.

Imminent climate risks

Climate model projections for the 21ᵗʰ to 23ʳᵈ centuries need to take paleoclimate evidence more fully into account, including the transient stadial effects of ice melt water flow into the oceans and amplifying feedbacks of global warming from land and oceans. Radiative forcing⁽²⁰], increasing with concentration of atmospheric greenhouse gases and rising by about 0.04 Watt/m²/year over the last 50 years⁽²¹⁾, totaled by more than 2 Watt/m², equivalent to ~3.0°C (~1.5°C per W/m²)⁽²²⁾. The rise of mean global temperatures to date by 0.9°C since 1880⁽²³⁾ therefore represents lag effect, pointing to potential temperature rise by approximately two degrees Celsius. A further rise in global temperatures would be enhanced by amplifying feedbacks from land and oceans, including exposure of water surfaces following sea ice melting, reduction of CO₂ concentration in water, release of methane and fires. Climate change trajectories would be highly irregular as a result of stadial events affected by flow of ice melt water into the oceans. Whereas similar temperature fluctuations and stadial events occurred during past interglacial periods (Cortese et al. 2007⁽²⁴⁾; Figure 6), when temperature fluctuations were close to ~1°C, further rises in temperature in future would enhance the intensity and frequency of extreme weather events, entering uncharted territory unlike any recorded during the Pleistocene, rendering large parts of the continents uninhabitable.

Figure 6. (A) Evolution of sea surface temperatures in 5 glacial-interglacial transitions recorded in ODP 1089
at the sub-Antarctic Atlantic Ocean. Lower grey lines – δ¹⁸O measured on Cibicidoides plankton;
Black lines – sea surface temperature. Marine isotope stage numbers are indicated on top of diagrams.
Note the stadial temperature drop events following interglacial peak temperatures, analogous
to the Younger Dryas preceding the onset of the Holocene (Cortese et al. 2007⁽²⁵⁾).
(B) Mean temperatures for the late Pleistocene and early Holocene.

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Andrew Glikson
by Andrew Glikson
Earth and Paleo-climate science, Australia National University (ANU) School of Anthropology and Archaeology,
ANU Planetary Science Institute,
ANU Climate Change Institute,
Honorary Associate Professor, Geothermal Energy Centre of Excellence, University of Queensland.



(1) IPCC, Special Report, Global Warming of 1.5 ºC

(2) Climate Council, Report, The good, the bad and the ugly: limiting temperature rise to 1.5°C

(3) Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming could be dangerous, by James Hansen et al.

(4) IPCC Climate Change 2013: Technical Summary, p.89

(5) Rapid changes of glacial climate simulated in a coupled climate model, by Andrey Ganopolski and Stefan Rahmstorf

(6) Coupled atmosphere-ice-ocean dynamics in Dansgaard-Oeschger events, by Camille Li and Andreas Born

(7) The last five glacial‐interglacial transitions: A high‐resolution 450,000‐year record from the subantarctic Atlantic, by G. Cortese, A. Abelmann and R. Gersonde

(8) Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming could be dangerous, by James Hansen et al. (2016)

(9) Regional acceleration in ice mass loss from Greenland and Antarctica using GRACE time‐variable gravity data, by I. Velicogna et al.

(10) Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise, by E. Rignot et al. (2011)

(11) Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming could be dangerous, by James Hansen et al.

(12) Sverdrup: Unit of flow – 1 Sv is equal to 1,000,000 m³ per second

(13) Eemian Interglacial Stage

(14) Giant boulders and Last Interglacial storm intensity in the North Atlantic, by Alessio Rovere et al. (2017)
Northern hemisphere winter storm tracks of the Eemian interglacial and the last glacial inception, by F. Kaspar (2006)

(15) Exceptional twentieth-century slowdown in Atlantic Ocean overturning circulation, by Stefan Rahmstorf et al. (2015)

(16) The UN's Devastating Climate Change Report Was Too Optimistic, by Nafeez Ahmed (Oct 16, 2018)

(17) IPCC Third Assessment Report, Working Group I: The Scientific Basis

(18) Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise, by E. Rignot et al. (2011)

(19) Mass balance of the Antarctic Ice Sheet from 1992 to 2017

(20) Radiative forcing – the difference between incoming radiation and radiation reflected back to space

(21) Climate Change in a Nutshell: The Gathering Storm, by James Hansen (18 December 2018)

(22) Target atmospheric CO2: Where should humanity aim?, by James Hansen (2008)

(23) NASA: Global temperature

(24) The last five glacial‐interglacial transitions: A high‐resolution 450,000‐year record from the subantarctic Atlantic, by G. Cortese, A. Abelmann and R. Gersonde

(25) The last five glacial‐interglacial transitions: A high‐resolution 450,000‐year record from the subantarctic Atlantic, by G. Cortese, A. Abelmann and R. Gersonde

This is an edited version of an article at Global Research
Copyright © Dr. Andrew Glikson, 2019

Saturday, January 5, 2019

The Gathering Climate Storm and the Media Cover-up | By Dr. Andrew Glikson

“Earth is now substantially out of energy balance. The amount of solar energy that Earth absorbs exceeds the energy radiated back to space. The principal manifestations of this energy imbalance are continued global warming on decadal time scales and continued increase in ocean heat content.” (James Hansen 2018)

“The people have no voice since they have no information” …“No First World country has ever managed to eliminate so entirely from its media all objectivity – much less dissent.” (Gore Vidal)

With the exception of the few who comprehend the nature of a Faustian Bargain[1], some billionaires, captains of industry and their political and media mouthpieces are driving humanity toward self-destruction through the two biggest enterprises on Earth, the fossil fuel industry, which is devastating the Earth atmosphere, and the industrial-military machine leading toward nuclear war. The rest of the world is dragged subconsciously, induced by bread and circuses.

[ 1880 - Feb. 2016 temperature anomaly from 1951-1980, source ]
By close analogy with the tobacco denial syndrome[2], albeit with consequences affecting the entire Earth, the fossil fuel industry has been paying climate pseudoscientists to propagate fabricated untruths regarding the origins and consequences of global warming, widely disseminated by the media.

Despite irrefutable evidence for global warming, such fabrications are still quoted by pro-coal lobbies and compliant politicians, including:
  1. Denial of basic laws of physics, i.e. the blackbody radiation laws of Plank, Stefan-Boltzmann and Kirchhoff[3]
  2. Denial of direct observations and measurements in nature, in particular the sharp rises of temperatures, ice melt rates, sea level rise and extreme weather events.
  3. Denial of the global warming origin of extreme weather events, i.e. the closely monitored rise in storms, hurricanes, fires and droughts in several parts of the world.[4]
  4. Denial of the bulk of the peer-reviewed literature summed up in the IPCC reports.
  5. Denial of conclusions of the world’s premier climate research organizations (NASA, NOAA, NSIDC (National Snow and Ice Data Centre), Hadley-Met, Tindale, Potsdam, WMO (World Meteorological Organization), CSIRO, BOM and other organizations).
In view of the rapidly growing direct evidence from the increase in extreme weather events, the common tactic has changed from outright denial to a minimization of the significance and consequences of the shift in state of the climate.

READ MORE: Crimes Against the Earth

Whereas news items channeled by international news agencies regarding extreme weather events are generally reported, at least by national broadcasters, the plethora of discussion and debate programs on TV and radio stations mostly overlook the enhanced toxic effects of carbon gases[5], or relegate it behind sports and entertainment news. In most instances discussion panels focus on the inside political machinations rather than the critical issues themselves.

According to Mary Debrett[6]:
“We are now in the middle of perfect storm of miscommunication about climate change. Various factors have converged to confound rational public conversation. Public opinion polling indicates that although there is widespread acceptance of climate change resulting from human activities, the public’s preparedness to pay for action to mitigate climate change is actually declining – even as climate scientists warn of the increasing urgency for action. These results signal a serious problem in the public communication of climate change. They reflect this perfect storm – where tensions between the media, politicians and various lobby groups have made it impossible for scientists and others with appropriate expertise, to cut through.”
The major influence the media exerts on public opinion[7], and the extent to which it can be referred to as the “tail which wags the political dog”, allows it nearly as much, or more, political power as political leaders, chief bureaucrats and heads of corporation. A power accompanied with little responsibility.


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[1] To “strike a Faustian bargain” is to be willing to sacrifice anything to satisfy a limitless desire for knowledge or power.







The original source of this article is Global Research.

Andrew Glikson
by Dr Andrew Glikson
Earth and Paleo-climate science, Australian National University (ANU)