New paper shows ocean ‘acidification’ was naturally about the same during the last interglacial period as today – Published in Quaternary Science Reviews
New paper shows ocean ‘acidification’ was about the same during the last interglacial period as today
http://hockeyschtick.blogspot.com/2013/10/new-paper-shows-ocean-acidification-was.html
A paper published today in Quaternary Science Reviews shows that reconstructed ocean pH during the last [Eemian] interglacial 130,000-114,000 years ago was naturally about the same as today [estimated alkaline pH of 8.14]. The paper also shows that the snail shell degradation index [LDX] was faster/greater during the last interglacial period than modern times, and increased at a faster rate during the last interglacial period than modern times. Thus, natural ocean ‘acidification’ was about the same as today, but increased at a faster rate and had a greater effect on dissolving shells during the last interglacial period in comparison to modern times.
The paper once again demonstrates alarmist claims about ocean ‘acidification’ are overblown.
Second graph from top shows reconstructed ocean pH was about the same during the last interglacial 130,000 – 114,000 years ago as today [estimated at 8.14 pH]. The snail shell degradation index [LDX] shown in bottom graph was faster/greater during the last interglacial period than modern times, and increased at a faster rate during the last interglacial period than modern times.
In-life pteropod shell dissolution as an indicator of past ocean carbonate saturation
Deborah Wall-Palmer, ,
Christopher W. Smart,
Malcolm B. Hart
School of Geography, Earth and Environmental Sciences, Plymouth University, Plymouth PL4 8AA, UK
Highlights
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In-life dissolution of fossil pteropod shells was examined using the LDX scale.
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Average shell diameter was used as an indicator of calcification rate.
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LDX shows significant correlation to CO2 and surface water carbonate concentration.
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Smaller, more corroded shells were found during interglacial periods.
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Larger, pristine shells were found during glacial periods.
Abstract
Recent concern over the effects of ocean acidification upon calcifying organisms has highlighted the aragonitic shelled thecosomatous pteropods as being at a high risk. Both in-situ and laboratory studies have shown that an increased dissolved CO2 concentration, leading to decreased water pH and low carbonate concentration, causes reduced calcification rates and enhanced dissolution in the shells of living pteropods. In fossil records unaffected by post-depositional dissolution, this in-life shell dissolution can be detected. Here we present the first evidence of variations of in-life pteropod shell dissolution due to variations in surface water carbonate concentration during the Late Pleistocene by analysing the surface layer of pteropod shells in marine sediment cores from the Caribbean Sea and Indian …
New paper finds European fire activity is at lowest levels of past 10,000 years – Published in Quaternary Science Reviews
New paper finds European fire activity is at lowest levels of past 10,000 years
http://hockeyschtick.blogspot.com/2013/10/new-paper-finds-european-fire-activity.html
A new paper published in Quaternary Science Reviews reconstructs fire activity in Central-Eastern Europe over the past 12,000 years and finds modern fire activity is near the lowest levels of the past 10,000 years. The paper adds to many others finding a long-term decrease in fire activity, despite claims of climate alarmists.
The paper also shows that reconstructed early and late summer temperatures in Central-Eastern Europe have both declined over the past ~10,000 years.
The US is currently experiencing the lowest fire activity in three decades, and the current New South Wales fires have nothing to do with CO2.
Reconstructed fire activity shown in top graph is at the lowest levels of the past 10,000 years. Reconstructed early and late summer temperatures in Central-Eastern Europe have declined over the past ~10,000 years, shown in 2nd graph from bottom. Horizontal axis is thousands of years before the present.
12,000-Years of fire regime drivers in the lowlands of Transylvania (Central-Eastern Europe): a data-model approach
A. Feurdeana, b, , , ,
J. Liakkab,
B. Vannièrec,
E. Marinovad,
S.M. Hutchinsone,
V. Mosburggera,
T. Hicklera, b, f
a Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, 60325 Frankfurt am Main, Germany
b Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325 Frankfurt am Main, Germany
c CNRS, UMR 6249 Chrono-Environnement, Université de Franche-Comté, 16 route de Gray, 25030 Besançon Cedex, France
d Centre for Archaeological Sciences, University of Leuven, Celestijnenlaan 200E, Bus 2408, 3001 Leuven, Belgium
e School of Environment and Life Sciences, University of Salford, Salford M5 4WT, UK
f Goethe University, Department of Physical Geography, Altenhöferallee 1, 60438 Frankfurt am Main, Germany
Highlights
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First multi-proxy record and climate modelling of fire regime in CE Europe.
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Strong influence of early summer temperature and moisture content on fire activity.
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High sensitivity of fire activity to the short-lived climate events.
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Frequent fires associated with open woodlands, whereas the decline in fire risk favoured woodland development.
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Synergic influence of natural and human factors on fire frequency from 3300 BP.
Abstract
The usefulness of sedimentary charcoal records to document centennial to millennial scale trends in aspects of fire regimes (frequency, severity) is widely acknowledged, yet the long-term variability in these regimes is poorly understood. Here, we use a high-resolution, multi-proxy analysis of a lacustrine sequence located in …
New paper finds summer temperatures in the year 2000 were about the same as during Medieval & Roman warm periods: Paper under open review for Climate of the Past
New paper finds summer temperatures in the year 2000 were about the same as during Medieval & Roman warm periods
http://hockeyschtick.blogspot.com/2013/10/new-paper-finds-summer-temperatures-in.html
A paper under open review for Climate of the Past reconstructs summer [June, July, August [JJA]] temperatures in Sweden and Finland over the past ~2,200 years and finds temperatures during the Medieval Warm Period 1,000 years ago and the Roman Warm Period 2,000 years ago were about the same as at the end of the 20th century. The paper also shows excellent agreement between the instrumental record since 1800 and the proxy reconstruction, unlike Michael Mann’s hockey stick “trick to hide the decline” in proxy temperatures after 1960. The paper adds to the published papers of over 1,200 scientists finding that the Medieval Warm Period was global and as warm or warmer than the present.
Fig. 8. Reconstruction of June, July, August [JJA] temperatures with 95% uncertainty levels. Temperatures during the Medieval Warm Period 1,000 years ago and the Roman Warm Period 2,000 years ago were the about same as at the end of the 20th century. Instrumental data from 1800 shown by black line.
Clim. Past Discuss., 9, 5659-5700, 2013www.clim-past-discuss.net/9/5659/2013/doi:10.5194/cpd-9-5659-2013
Testing long-term summer temperature reconstruction based on maximum density chronologies obtained by reanalysis of tree-ring datasets from northernmost Sweden and Finland
V. V. Matskovsky1 and S. Helama21Institute of Geography, Russian Academy of Sciences, Moscow, Russia2Finnish Forest Research Institute, Northern Unit, Rovaniemi, FinlandAbstract. Here we analysed the maximum latewood density (MXD) chronologies of two published tree-ring datasets: from Torneträsk region in northernmost Sweden (TORN, Melvin et al., 2013) and from northern Fennoscandia (FENN, Esper et al., 2012). We paid particular attention to the MXD low-frequency variations to reconstruct long-term summer (June–August, JJA) temperature history. We used published methods of tree-ring standardization: regional curve (RC) standardization, combined with signal-free (SF) implementation. Comparisons with a single-RC (RC1) and multiple-RC (RC2) were also carried out. We develop a novel method of standardization, the correction (C) implementation to SF (hence, RC1SFC or RC2SFC), tailored for detection of pure low-frequency signal in tree-ring chronologies. In this method, the error in RC1SF (or RC2SF) chronology, is analytically assessed and extracted to produce a RC1SFC or RC2SFC chronology. In TORN, the RC1SF chronology shows higher correlation with summer temperature (JJA) than RC1SFC, whereas in FENN the temperature signals of RC1SF chronology is improved by correction implementation (RC1SFC). The highest correlation between differently standardized chronologies for two …
New paper finds 4 Alaskan glaciers are about the same size as during the Medieval Warm Period
New paper finds 4 Alaskan glaciers are about the same size as during the Medieval Warm Period
http://hockeyschtick.blogspot.com/2013/10/new-paper-finds-4-alaskan-glaciers-are.html
A paper published today in Quaternary Science Reviews reconstructs the size of four glaciers in Alaska over the past 1500-2000 years. For each of the four glaciers, the authors find the termination point at the end of the record in the late 20th century was approximately the same as during the Medieval Warm Period ~1,000 years ago. According to the paper, the data “supports solar irradiance as the primary pacemaker for centennial-scale fluctuations of mid-latitude valley glaciers prior to the 20th century.” The authors find all four glaciers advanced during the Little Ice Age, which was the coldest period of the past 10,000 years, and have regressed during the recovery from the LIA to termination points similar to those during the Medieval Warm Period.
Glacier regression from the Holocene maximum shown for 4 Alaskan glaciers. Total Solar Irradiance shown in orange graph, volcanic activity by black graph.
Late Holocene glacial history of the Copper River Delta, coastal south-central Alaska, and controls on valley glacier fluctuations
David J. Barclaya, , ,
Elowyn M. Yagerb,
Jason Gravesa,
Michael Kloczkoa,
Parker E. Calkinc
a Geology Department, SUNY Cortland, Cortland, NY 13045, USA
b Center for Ecohydraulics Research, Department of Civil Engineering, University of Idaho, Boise, ID 83702, USA
c INSTAAR, University of Colorado at Boulder, Boulder, CO 80309, USA
Highlights
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Late Holocene histories were reconstructed for four valley glaciers in Alaska.
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Tree-ring based dating methods provide high temporal and spatial resolution.
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Glacier termini have made four major advances in the past 2000 years.
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Solar output paced mid-latitude valley glacier fluctuations in late Holocene.
Abstract
Fluctuations of four valley glaciers in coastal south-central Alaska are reconstructed for the past two millennia. Tree-ring crossdates on 216 glacially killed stumps and logs provide the primary age control, and are integrated with glacial stratigraphy, ages of living trees on extant landforms, and historic forefield photographs to constrain former ice margin positions. Sheridan Glacier shows four distinct phases of advance: in the 530s to c.640s in the First Millennium A.D., and the 1240s to 1280s, 1510s to 1700s, and c.1810s to 1860s during the Little Ice Age (LIA). The latter two LIA advances are also recorded on the forefields of nearby Scott, Sherman and Saddlebag glaciers. Comparison of the Sheridan record with other two-millennia long tree-ring …
Forecasting Expert: UN IPCC climate modeling procedures need serious re-modeling
IPCC climate modeling procedures need serious re-modeling
http://www.cfact.org/2013/10/22/ipcc-climate-modeling-procedures-need-serious-re-modeling/
Everyone ought to be very skeptical of the Intergovernmental Panel on Climate Change once they learn that the IPCC violated 72 of 89 relevant forecasting principles in creating its climate change projections. As Australian forecasting guru Kesten Green explains, “(T)here really is no excuse for the negligence IPCC has shown in overlooking the findings of nearly a century of research on forecasting methods in addressing matters so vital to the public interest.”
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Those Stubborn Facts: ‘Unprecedented’ Modern Temperatures Claim Proving To Be False, Scientists Discover
Those Stubborn Facts: “Unprecedented” Modern Temperatures Claim Proving To Be False, Scientists Discover
Climate history is replete with peer reviewed research and historical anecdotal evidence that both the Roman and Medieval warming eras were likely warmer than current modern temperatures. This new study (see adjacent plot) adds to the cornucopia of empirical evidence…
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