Sentences with phrase «paleoclimate model»

This will facilitate the creation of targeted observational networks, provide test beds for reconstruction methods, and enable comparisons with paleoclimate model simulations.

Coats, S., 2015: Paleoclimate Model - Data Comparisons of Hydroclimate over North America with a Focus on Megadroughts.

Cochelin et al used a model of intermediate complexity to show that the orbital variations over the next 100,000 years are weak enough that even a little human CO2 remaining in the atmosphere is enough to keep the earth out of an ice age («Simulation of long - term future climate changes with the green McGill paleoclimate model: The next glacial inception»).

Previous paleoclimate modeling studies suggest the volcanic spurts could have wiped out the ozone layer worldwide, though temporarily.

«Applying the same technique to other subglacial volcanos will provide new constraints on paleoclimate models that consider the extents and timing of planetary glaciations.»

However, the quantitative response to freshwater inputs varies widely among models (Stouffer et al., 2006), which led the CMIP and Paleoclimate Modelling Intercomparison Project (PMIP) panels to design and support a set of coordinated experiments to study this issue (http://www.gfdl.noaa.gov/~kd/CMIP.html and http://www.pmip2.cnrs-gif.fr/pmip2/design/experiments/waterhosing.shtml).

Paleoclimate Modelling Intercomparison Project 2 (PMIP - 2) simulations shown in bottom left and right panels do not include the radiative influences of LGM changes in mineral dust or vegetation.

I have never seen this weather pattern except in theoretical paleoclimate models.

Two time periods analysed in the Paleoclimate Modelling Intercomparison Project (PMIP, Joussaume and Taylor, 1995; PMIP2, Harrison et al., 2002) are also considered, the mid-Holocene (6 ka) and the LGM (21 ka).

I am working with Dr. Katrin Meissner, who primarily studies ocean, carbon cycle, and paleoclimate modelling.

To better understand these discrepancies, a recent study published in Geophysical Research Letters investigates the drivers of changes in deep ocean circulation across a range of modern and Last Glacial Maximum (LGM, ~ 21000 years ago) climate simulations from the latest Paleoclimate Modelling Intercomparison Project (PMIP).

Coupled global climate models, such as those that participated in the Paleoclimate Modeling Intercomparison Project (PMIP)(Jansen et al., 2007), in combination with improved paleo - climate records have led to better appreciation of the extent of extreme events that have occurred in the past (e.g., Cook et al., 2010b).

My main research interest is in pre-Quaternary paleoclimate modeling.

First, there is a need to test and validate paleoclimate models using the climate record stored in sediments (Moore et al., 1992).

Raymond S. Bradley provides his readers with a comprehensive and up - to - date review of all of the important methods used in paleoclimatic reconstruction, dating and paleoclimate modeling.

Not exact matches

«This will evolve,» Putnam said, as more paleoclimate records emerge and are paired with climate models to «try to see if climate models can reproduce the patterns that we see in those datasets.»

In order to predict future changes in climate, scientists verify and refine their models against paleoclimate data from the ice cores Taylor and others pull up.

The paleoclimate data, which included mainly changes in the oxygen isotopes of the calcium carbonate deposits, were then compared to similar records from other caves, ice cores, and sediment records as well as model predictions for water availability in the Middle East and west central Asia today and into the future.

However, studies evaluating model performance on key observed processes and paleoclimate evidence suggest that the higher end of sensitivity is more likely, partially conflicting with the studies based on the recent transient observed warming.

The match of his model to actual paleoclimate is impressive, but that doesn't necessarily mean it's right — especially since Huybers made no suggestion about what the physical mechanism is which brings this about.

However, values this low are inconsistent with numerous studies using a wide variety of methods, including (i) paleoclimate data, (ii) recent empirical data, and (iii) generally accepted climate models.

Marchal, O., T.F. Stocker, and F. Joos, 1998: A latitude - depth, circulation - biogeochemical ocean model for paleoclimate studies.

Stocker, T.F., D.G. Wright, and L.A. Mysak, 1992: A zonally averaged, coupled atmosphere - ocean model for paleoclimate studies.

This is being actively investigated for the current human - caused global warming scenario with models and paleoclimate data.

Our approach is a significant advance on previous models, as we incorporate the lake index as a proxy for local climate, together with regional and global paleoclimate records.

In the response by raypierre - I agree about the problems with simple energy balance model and its lack of spatial representation, but it's tough to fault the authors for the lack of cloud detail, since the science is not up to the task of solving that problem (and doing so would be outside the scope of the paper; very few paleoclimate papers that tackle the sensitivity issue do much with clouds).

To identify best fit models relating paleoclimate to both the lake index and hominin evolution, we used a the stepAIC function in R package MASS to select the best fit model [38], see Figure 2.

Here we use a comprehensive set of paleoclimate indicators: East African Rift lake presence, regional Aeolian flux records from the Arabian Sea, the Mediterranean and the East Atlantic together global benthic foraminifera δ18O with to develop models predicting hominin brain size.

The slow feedbacks are difficult to model, but paleoclimate data and observations of ongoing changes help provide quantification.

In contrast, chemistry modeling and paleoclimate records [222] show that trace gases increase with global warming, making it unlikely that overall atmospheric CH4 will decrease even if a decrease is achieved in anthropogenic CH4 sources.

It's a long paper with a long title: «Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 oC global warming could be dangerous».

«Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2o C global warming could be dangerous»

Climate model studies and empirical analyses of paleoclimate data can provide estimates of the amplification of climate sensitivity caused by slow feedbacks, excluding the singular mechanisms that caused the hyperthermal events.

The full title is: «Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 o C global warming could be dangerous ``.

I would like to see this evidence that models just based on known physics «model climate and paleoclimate rather well».

There are tons of studies — ranging from paleoclimate studies to studies of volcanic effects, etc. that constrain climate response and which generally yield results consistent with the models.

The problem with the paleoclimate ice sheet models is that they do not generally contain the physics of ice streams, effects of surface melt descending through crevasses and lubricating basal flow, or realistic interactions with the ocean.

One can temper that with studies of paleoclimate sensitivity, but the ensemble results still should be borne in mind, since doubling CO2 takes us into a climate that has no real precendent in the part of the climate record which has been used for exploring model sensitivity, and in many regards may not have any real precedent in the entire history of the planet (in terms of initial condition and rapidity of GHG increase).

There are plenty of other examples, and of course, there is a lot of intrinsic interest in paleoclimate that is not related to climate models at all!

David B. Benson: The evidence is that the GCMs, being based on physics, model climate and paleoclimate rather well.

On July 23, I wrote about the rocky rollout, prior to peer review, of «Ice Melt, Sea Level Rise and Superstorms: Evidence from Paleoclimate Data, Climate Modeling, and Modern Observations that 2 °C Global Warming is Highly Dangerous.»

David's comments reminded me of something that Suki Manabe and I wrote more than 25 years ago in a paper that used CLIMAP data in a comparative evaluation of two versions of the 1980s - vintage GFDL model: «Until this disparity in the estimates of LGM paleoclimate is resolved, it is difficult to use data from the LGM to evaluate differences in low latitude sensitivity between climate models.»

[A quick note on terminology: All constraints have to be based on observations of some sort (historical trends, specific processes, paleoclimate etc.) and all constraints involve models of varying degrees of complexity to connect the observation to the sensitivity metric.

In fact, the true test of climate models is paleoclimate reconstruction, in which they have been rather successful.

Summary for Policymakers Chapter 1: Introduction Chapter 2: Observations: Atmosphere and Surface Chapter 3: Observations: Ocean Chapter 4: Observations: Cryosphere Chapter 5: Information from Paleoclimate Archives Chapter 6: Carbon and Other Biogeochemical Cycles Chapter 7: Clouds and Aerosols Chapter 8: Anthropogenic and Natural Radiative Forcing Chapter 8 Supplement Chapter 9: Evaluation of Climate Models Chapter 10: Detection and Attribution of Climate Change: from Global to Regional Chapter 11: Near - term Climate Change: Projections and Predictability Chapter 12: Long - term Climate Change: Projections, Commitments and Irreversibility Chapter 13: Sea Level Change Chapter 14: Climate Phenomena and their Relevance for Future Regional Climate Change Chapter 14 Supplement Technical Summary

I suspect that there will be considerably more uncertainty attached to this activity than there was to the attribution of climate change to anthropogenic activity — in part because the only guides we really have are the models and paleoclimate studies, both of which are subject to significant uncertainties.

Proxy data, ratonal behind the models, how they have improved and some issues on paleoclimate are all covered.

This might partly be explained by the fact that paleoclimate data is measuring a system in equilibrium, while models are predicting a climate in transition.

As we have discussed several times elsewhere on this site, studies employing model simulations of the past millennium have been extremely successful in reproducing many of the details evident in paleoclimate reconstructions of this interval as a forced response of the climate to natural (primarly volcanic and solar) and in more recent centuries, anthropogenic, radiative changes.

Even if a climate model is successful in paleoclimate reconstruction it may fail badly in its prediction for this century and beyond.