- Kenneth M Towe added an answer:5What is the origin of Atlantic Multidecadal Oscillation (AMO)?
I am interested in the theories and evidence linking the AMO to Atlantic Meridional Overturning Circulation, solar forcing and possibly other causes in explaining this phenomenon. Is there literature reviewing these mechanisms? Do you have links to relevant net sources.Following
- Malcolm B. Hart added an answer:20Can anybody suggest methods for the study of Cretaceous benthic foraminifera (apart from thin section studies)?
How to study Cretaceous benthic foraminifera from fragile carbonate material? You can also suggest suitable literature.
While all the suggestions are sensible and well tried, you need to work up the scale of physical/chemical aggressiveness. Begin with the most benign and then judge the effectiveness.Following
- Jane R Foster added an answer:11Does any university organize international courses or summer schools on palaeoclimatology in this coming year 2016?
I am looking for information on advanced courses in English that would be open for graduate or post-graduate level foreign students. This would be interesting for students specializing on climate reconstruction, past climate dynamics, current issues of climatology, and so on. Is there any web-sites listing such activities?
I saw this tweet today: TRACE2016: Tree Rings in Archaeology, Climatology and Ecology. Białowieża (Poland) 11-15 May 2016 http://www.trace2016.comFollowing
- Dimis Poulos added an answer:21What are the origins of DeVries (~200 year) and Gleissberg (~83 year) solar cycles?I am trying to find information on DeVries (~200 year) and Gleissberg (~83 year) solar cycles. What is their origin? Are these manifestations of the 11 year sunspot cycle or some other mechanism? A pointer to any publications much appreciated.
with my approach you can predict solar cycles for the next several thousands of years for as long as you have astronomical data since I have documented the planetary gravitational tidal origin of solar cycles and solar wind
- Malcolm B. Hart added an answer:3What is your opinion on the role of paleoclimate in the cretaceous-paleogene mass extinction?I need to know about the role of paleoclimate in that time interval and how it affected the distribution of vertebrates.
You seem to have everything in that long account, but very jumbled! Yes it was a greenhouse period. Sea levels had lowered after the CRETACEOUS maximum in the Turonian. There was a tsunami, but do not believe every 'wild' statement about its size. There is an erosion surface in Texas, and some erosion, but not that excessive. The plankton was most badly affected, possibly by ocean acidification event that lasted only a few thousands of years. In some of the lowermost Paleocene in Texas the foraminifera, post-impact were actually quite large and do not show dwarfism. See account in my 2014 paper in the Gulf Coast Transactions.Following
- Gianna Vivaldo added an answer:12Any advice on climate field reconstruction in extracting frequency-dependent signals?
Proxies generally record frequency-dependent climate signals. I would think that this frequency aspect is perhaps handled by careful selection of proxies or by e.g. choosing proper indexing methods if tree-rings are concerned. Do any of the approaches called climate field reconstruction (CFR methodologies) have clear advantages in this respect? Opinions, views and relevant references welcome!
Dear Prof. Lindholm,
there are several approaches to cycles detection in a given time series. You can start from "classical/older" ones, such as Fast Fourier Transform, continuous wavelets transform, maximum entropy methods; or you can apply some more recent techniques (multi-taper methods, singular-spectrum analysis). If you need an help, feel free to contact me directly, since the field is a very huge one (digital signal processing and spectral analysis).
Have a nice day,
- Zhifang Xiong added an answer:4Who can tell me which publications presented the temperature in Philippines since the Last Glacial Maximum? Thank you!
I mean the temperature in the Philippine islands or its ambient maritime landmasses rather than its ambient surface ocean.
Dear Prof. Stigter, Thank you very much!Following
- Eimi Ailen Font Caligiore added an answer:4Can anyone help me with information/publications of the genus: Pupoides Pfeiffer, 1854 (ecology, distribution, etc.)?
I need more information for paleoclimatic reconstruction. The shells were found in Holocene sediments from central-western Argentina
Thank you very much! unfortunatelly there´s scarce information of Pupillidae in Argentina, and particulary I haven´t found any of PupoidesFollowing
- Guoyu Ren added an answer:11Can someone help me to know more about paleoclimatology methods to reconstruction of past climate of the Earth?
I'm interested to know more about this field. Can someone help me to know more about paleoclimatology methods to reconstruction of past climate of the Earth?
You could read one or more text books. "Paleoclimatology" by Raymond S. Bradley is a good one for a general understanding of paleoclimatology. You should also be clear what time-scales and objectives you are going to focus on, and choose to read the specific books or papers in your field.Following
- Francesco Maspero added an answer:1After sampling of tree rings, where we can put the samples before isotopic analysis?
You can put them in clean aluminum foil. Then it is possible to transfer the pack in boxes or bags, and send them to the lab.Following
- Kenneth M Towe added an answer:5How can I explain the relationship between the CCD, pCO2, ice-sheet expansion at the E/O boundary at ~34 Ma?
Please look at the attached figure (Heiko Palike et al., 2012, nature). At ~34 Ma, we can find the CCD deepening, carbonate accumulation, pCO2 decreasing, ice-sheet expansion, and Antarcitic cooling. Mybe the trigger was ice-sheet expansion induced by low insolation. If the decrease of the pCO2 was uptaked by ocean, will be not good for carbonate accumulation. Isn't that a bit of a contradiction? How about the relationship between these variations? Thank you very much!Following
- Homma Rostami added an answer:4What proxy is useful to find out about drought during the Holocene in the Eastern Arabian Sea?
I use marine sediments to find out drought during the Holocene in the Eastern Arabian Sea. What are the data useful to support my objective?
use of dendrology is very useful.drought during the Holocene in the Eastern Arabian Sea had many effects on dendroclimatology.i worked on demdroclimatology of Asian environment and i found many interesting resaults.Following
- Antonio Flores Díaz added an answer:25Which types of climate proxies are able to show seasonality changes in the Holocene climate?
Is it possible to demonstrate seasonality changes in the climates using non-laminated sediment cores? If so, which climate proxies are suitable for this purpose?
In sediments and alluvial soils and lake sediments can be seen this kind of change by varying the deposition of salts and mineralogy and particle size of the materials.Following
- Christopher C. Sorlien added an answer:4Can you provide information about erosion of huge ice stream/piedmont glacier troughs?
S. Davis, me, et al 2014 AGU abstract proposed that a 400 km-long, 50 km-wide pre-30 Ma buried erosional and rift trough in Ross Sea could have last been eroded by ice, and this ice could have been from the earliest (33 Ma) East and/or West Antarctic Ice sheet. This was very controversial among our co-authors, and we allowed other possibilities, such as River erosion after rifting ceased, assuming restoring differential subsidence removes the huge reverse gradients of the major unconformity along the trough axes.
Related to this:
Question 1: Is large (Piedmont) glacial or ice stream erosion like River erosion, where the ice can cut down on the order of 1 km in 1 or 2 million years if out of equilibrium in one direction (while the bed would instead aggrade if out of equilibrium in the other direction. I know that cold-based ice streams/glaciers are frozen to their beds and do not erode.
Question 2: Do you know of examples of 50 km-wide and >500 m deep troughs known to be deeply eroded by ice in a couple of million years or less? I’m thinking Northern Hemisphere like Greenland, because ice had not been there for tens of millions of years. Laurentian Trough on the shelf of Atlantic Canada may be one example, but I have not been able to find papers or seismic reflection data that show the base of the sub-bottom trough (we have figures of the sea floor trough, which is 50 km-wide but only a couple of hundred meters deep.
I am being a bit lazy; I have an abstract deadline on this in a week and just have not had time to focus on looking into the literature because I have had to spend my time on the Ross Sea interpretation and other projects.
(Davis et al is a student abstract; is my project).
Thank you. this is useful. But, I suspect that most Norwegian fjords do not have the large scale of what I am studying: 50 km-wide eroded trough (hundreds of km-long). We are making progress on our paleotopography/bathymetry, but it is likely that the Ross Sea pre-30 Ma erosion had to cut to about 2 km below paleo-sea level (generally less, but in middle of the 2 closed basins, maybe 2 km).
If you have any references on such large troughs, please post them.
- Wolfram Meier-Augenstein added an answer:5Can someone recommend an IRMS use methodology ?Stable isotope analysis
What instrumental methodology (IRMS or Laser CRDS) is best suited will depend on your application. Laser CRDS systems are less expensive than IRMS systems but are limited to analysis of CO2 (13C; 18O) and water (2H; 18O). IRMS systems can be coupled to gas chromatographs (2H, 13C, 15N, 18O), HPLC (13C only), elemental analyzer (13C, 15N, 34S) and high temperature conversion elemental analyzer (2H, 18O).
For a comprehensive guide to IRMS methodology have a look at this guide:
forensic-isotopes.org/assets/IRMS Guide Finalv3.1_Web.pdfFollowing
- Carmen Fraticelli added an answer:7Can anyone help me with Cenozoic European paleomaps that are or can be geo-referenced?
I need European maps for the Cenozoic that can be used in GIS to plot fossil data.
Actually, what you need is a plate model first. Fossil data should be plotted (in GIS) on present day maps. Then you reconstruct them back to a specific time period (Cenozoic is too broad). The second overlay is the depositional environments followed by the paleotopography/bathymetry. You can, in this way, also test the validity of the paleoenviromental maps.Following
- Natalia S Duxbury added an answer:9Does anyone have data about weight ice content (ice wedges, massive ice bodies and segregation ice) and bulk density in Arctic permafrost deposits?
Papers, references, databases? Quaternary deposits of Beringia region (from Taymir to Alaska) are interest for me....
Articles by V. E. Romanovsky and me on this ResGate, also D. Nicolsky and other members of the V. E. Romanovsky's group at the UAF, Alaska.Following
- Selvaraj Kandasamy added an answer:3Does anyone know how the westerlies affect the central Tibetan Plateau where the precipitation dominated by Indian Summer Monsoon?
There are a lot of literatures suggest that the westerlies could take precipitation into the central Tibetan Plateau and far more eastern areas during the cold period. Do anyone give some evidence?
Please check the paper on Holocene moisture evolution in arid central Asia and its out of phase relationship with Asian monsoon history by Chen, F.H. et al. published in the year 2008. They discussed the influence of Westerlies in arid China during the Holocene, though they are not entertained any discussion of the Westerlies on the Tibet, in particular.Following
- Antonio Fernando Menezes Freire added an answer:5How can I estimate paleotemperatures based on oxygen isotopes of dolomite cement? Could someone point me to a good reference?
How can I estimate paleotemperatures based on oxygen isotopes of dolomite cement? Could someone point me to a good reference?
- Richard Stern added an answer:4Where can I find estimated Global Sea-level history data sets for the past 140,000 years?
I want to plot global sea level changes for the past 140,000 to determine trends in marine taxa radiations in the oceans. I have been unable to find data sets from NOAA.
Not sure if you are looking for an already completed dataset for global changes, or trying to compile it from regional sources....at any rate, here are a few references mostly from the circumpolar world with "sea-level" in the title. Cheers, Richard
Moore, G. W.
1960 Recent Eustatic Sea-Level Fluctuations Recorded by Arctic Beach Ridges. In U.S. Geological Survey Research, 1960, pp. B355-357. U.S. Geological Survey Professional Paper 400, U.S. Geological Survey, Washington, D.C.
Hume, James D.
1965 Sea-level Changes During the Last 2000 Years at Point Barrow, Alaska. Science 150:1165-1166.
Kind, N. V.
1973 Late Quaternary Climatic Changes, Sea-level Fluctuations and Glacial Events of the Old and New World: Geochronology According to Isotopic Data. In The Bering Land Bridge and Its Role for the History of Holarctic Faunas in the Late Cenozoic (Abstracts), Academy of Sciences of U.S.S.R., Far-Eastern Scientific Center, Khabarovsk.
McManus, Dean A. and Joe S. Creager
1984 Sea-Level Data for Parts of the Bering-Chukchi Shelves of Beringia from 19,000 to 10,000 14C Yr B.P. Quaternary Research 21:317-325.
Shennan, I., M. J. Tooley, M. J. Davis and A. Haggart
1983 Analysis and Interpretation of Holocene Sea-Level Data. Nature 302:404-410.
Searle, D. J. and P. J. Woods
1986 Detailed Documentation of a Holocene Sea-Level Record in the Perth Region, Southwestern Australia. Quaternary Research 26(1):299-308.
Shugar, Dan H., Iam J. Walker, Olav B. Lian, Jordan B.R. Eamer, Christina Neudorf, Duncan McLaren and Daryl Fedje
2014 Post-glacial Sea-level Change Along the Pacific Coast of North America. Quaternary Science Reviews 97(2014):170-192.Following
- P.J. Mudie added an answer:6What age correction is needed for mollusc C-14 dates from Black and Marmara Sea lacustrine phases?
High resolution dating of events in the Black and Marmara Seas during non-marine phases requires appropriate correction of C-14 ages because shells are not in equilibrium with global values of ca. 400 yr. Proposed values range from 0 (fully mixed, in equilibrium with atmosphere, no correction needed) to 1000 yrs (benthos contain old bottom water or river transported carbon). Peat (grows in equilbrium with atmosphere) compared to in-situ shell from the same sample indicates a reservoir correction of ca. 850 yrs is needed for shells. Which correction value is correct for A) Black Sea? B) Marmara Sea with overflow water.
Thanks for all your answers. In Marmara Sea we have new cores with lacustrine sediment containing shells next to tephra layers dated by wood. These may provide a more accurate reservoir correction value for the late Pleistocene interval.Following
- Sidney Ash added an answer:13Could any Palaeobotanist help me to identify the ancient plants?
The picture was taken from a piece of core in the late Triassic Ordos basin. Could any Palaeobotanist please help me to identify the ancient plants and list its implications for paleoclimate : in the late Triassic Ordos Basin, central China. It deposited in deltaic or lacustrine environment. I want to know its Latin name and implications for paleoclimate. Thanks a lot!
I agree with Han, we need a better picture.Following
- Zhitong Yu added an answer:1Can a modeler help me test my hypothesis using a model (such as GCM) to modified topography ?
I infer that there probably existed a passage between the Tibetan Plateau and the Qinling Mountains during the Late Miocene based a lot of tectonic and climatic records. Development of the passage was mainly controlled by the eastward expansion of the Tibetan Plateau, which constrained rainfall transported by the Asian summer monsoon to flow into interior China. I need a modeler help me to test this hypothesis? Please contact me for specific information
- Jamal Munshi added an answer:7What is the 1-sigma and 2-sigma error in radiocarbon dating?What is 1-sigma and 2-sigma error in the radiocarbon dating and how to decide which error range we should use for the data set?
I think we should stick to probability based confidence intervals such as the commonly used 95% CI. This is what I have done in my paper on radiocarbon dating which I believe is available on Researchgate and if not it may also be found at
- Massih Afghah added an answer:3Is there any hard evidence concerning the thickness of the Precambrian troposphere?
Simply, I’m looking for papers that gives me knowledge about any models or assumption concerning the thickness of troposphere of Early Atmosphere, e.i. during the Neo-, Meso- and PaleoProterozoic?
Thanks in advance, Zbyszek
I think the attached paper is useful for your question
- Fadhil A. Lawa added an answer:1Can anyone suggest how the ecological functioning of PETM and Early Eocene climatic optimum can add value to E & P of hydrocarbon?
Distinguished Colleague, am working on the ECOLOGICAL FUNCTIONING OF ZOO AND PHYTOPLANKTON COMMUNITIES ACROSS THE PALEOCENE-EOCENE HYPER THERMAL EVENTS. Can anyone suggest how this can add value to petroleum exploration and production?
The PETM can influence the organic material in this boundary and its quite common in iran at the Top of Pabdeh Formation ,where its also responsible for oil generations in certain oil fieldsFollowing
- Chris Gueymard added an answer:6What is the difference between insolation and solar irradiance?
In paleoclimate research, there always talking about the forcing factors, such as insolation and solar irradiance. However, I could not make it clear the difference between them. I have some knowledge about the latter one, which indicate the activity of the sun, such as sunspot, and could be measured by 10Be and 14C.
Could you shared some of your opinions on this? Thanks.
Insolation is a vague colloquial term, not a scientific quantity--at least not anymore
The terms to use are either irradiance (W/m2) or irradiation for accumulated energy over time (MJ/m2 or kWh.m2)Following
- Erman Özsayin added an answer:7Where can I get a detailed map of the Triassic of India?
Does anyone know of detailed geologic maps of India? Thanks in advance...
Do you need a specific scale?Following
- Boaz Lazar added an answer:2Does anyone know "Increased carbonate production and burial in epeiric seas，decreasing the [CO32-],leading to the positive d18O excursions ?
It is about stable isotope geochemistry
CaCO3 precipitation decreases the carbonate alkalinity (HCO3-+2*CO32-) and not the CO32- alone. Precipitation of CaCO3 however increases the partial pressure of CO2 in the sea (Ca2++HCO3-=CaCO3(s)+CO2(aq)+H2O) that may l escape to the atmosphere and taken up by the phytoplankton population both leading to increase in the 13C/12C of seawater DIC (dissolved inorganic carbon) and no significant change in the 18O/16O ratio, as indicated by Julie in the answer above. In epeiric sea the situation is more complicated because also changes in the alkalinity input from the nearby land masses may shift the carbon balance of the sea.
Hope that it helped,
Paleoclimatology (palaeoclimatology) is the study of changes in climate taken on the scale of the entire history of Earth.