Category Archives: climate models

Global climate models and the laws of physics

by Dan Hughes

We frequently see the simple statement, “The Laws of Physics”, invoked as the canonical summary of the status of the theoretical basis of GCMs.

Continue reading

Climate policy: Fake it ’til you make it

by Judith Curry

The economic models that are used to inform climate policy currently contain an unhealthy dose of wishful thinking. Technologies that remove carbon dioxide from the air are assumed in the models that avoid dangerous climate change – but such technologies do not yet exist and it is unclear whether they could be deployed at a meaningful scale. – Tim Kruger

Continue reading

The art and science of climate model tuning

by Judith Curry

We survey the rationale and diversity of approaches for tuning, a fundamental aspect of climate modeling which should be more systematically documented and taken into account in multi-model analysis. – Hourdin et al.

Continue reading

Atmospheric Radiation Measurement Program

by Judith Curry

The first 20 years.

Continue reading

On the likelihood of recent record warmth

by Judith Curry

[O]ur results suggest that the recent record temperature years are are roughly 600 to 130,000 times more likely to have occurred under conditions of anthropogenic than in its absence.  – Mann et al.

Continue reading

Huge efficacy of land use forcing in one GISS-E2-R simulation: is an ocean model error involved?

by Nic Lewis

In a recent article here, which summarised a longer piece at ClimateAudit, I discussed the December 2015 Marvel et al.[1] paper, which contends that estimates of the transient climate response (TCR) and equilibrium climate sensitivity (ECS) derived from recent observations of changes in global mean surface temperature (GMST) are biased low.

Continue reading

Climate models and precautionary measures

by Judith Curry

Ergo, we should build down CO2 emissions, even regardless of what climate-models tell us. – Nassim Taleb

Continue reading

Climate models versus climate reality

by Pat Michaels and Chip Knappenberger

Perhaps the most frank example of the growing disconnection between forecast and observed climate change was presented by University of Alabama’s John Christy to the Senate Subcommittee on Space, Science, and Competitiveness Committee of the U.S. House of Representatives on December 8.

Continue reading

New research on atmospheric radiative transfer

by Judith Curry

Three new papers highlight how atmospheric radiative transfer, particularly how it is treated in climate models, is not ‘settled science.’

Continue reading

Questioning the robustness of the climate modeling paradigm

by Judith Curry

Are climate models the best tools? A recent Ph.D. thesis from The Netherlands provides strong arguments for ‘no’.

Continue reading

Applications of subseasonal weather forecasts

by Judith Curry

There is growing interest in the scientific, operational and applications communities in developing forecasts that fill the gap between medium range weather forecasts (up to two weeks) and seasonal forecasts (3-6 months).

Continue reading

Will a return of rising temperatures validate the climate models?

by Donald C. Morton

The coincidence of the current plateau in global surface temperatures with the continuing rise in the atmospheric concentration of carbon dioxide has raised many questions about the climate models and their forecasts of serious anthropogenic global warming.

Continue reading

Model structural uncertainty – are GCMs the best tools?

by Judith Curry

Rarely are the following questions asked:  Is the approach that we are taking to climate modeling adequate?  Could other model structural forms be more useful for advancing climate science and informing policy?

Continue reading

On the AR4’s projected 0.2C/decade temperature increase

by Judith Curry

“For the next two decades a warming of about 0.2C per decade is expected for a range of emission scenarios.” – IPCC AR4

Continue reading

The heart of the climate dynamics debate

by Judith Curry

Lennart Bengtsson’s recent statement on climate research has elicited a response from Andy Lacis, that directly points to the fundamental debate in climate dynamics.

Continue reading

How simple is simple?

by Tomas Milanovic

This essay has been motivated by Isaac Held’s paper [link] arguing for possible emerging simplicity or even linearity in climate dynamics.

Continue reading

UK-US Workshop Part IV: Limits of climate models for adaptation decision making

by Judith Curry

This post discusses Workshop presentations on the utility of climate models for regional adaptation decisions.

Continue reading

How far should we trust models?

by Judith Curry

In economics, climate science and public health, computer models help us decide how to act. But can we trust them? – Jon Turney

Continue reading

Workshop on the Roles of Climate Models

by Judith Curry

I am in the Netherlands, attending a Workshop on The Roles of Climate Models: Epistemic, Ethical, and  Socio-political Perspectives.

Continue reading

Implications for climate models of their disagreement with observations

by Judith Curry

How should we interpret the growing disagreement between observations and climate model projections in the first decades of the 21st century?  What does this disagreement imply for the epistemology of climate models?

Continue reading

Spinning the climate model – observation comparison: Part II

by Judith Curry

IPCC model global warming projections have done much better than you think. – Dana Nuccitelli

Continue reading

Nic Lewis on the UK Met Office on the pause

by Nic Lewis

These comments constitute a response to erroneous statements and misrepresentations made in a report published by the Met Office in July 2013: “The recent pause in global warming (3): What are the implications for projections of future warming?” (the Report).

Continue reading

Pause tied to equatorial Pacific surface cooling

by Judith Curry

Update:  New comment from Xie

My mind has been blown by a new paper just published in Nature.

Continue reading

Overestimated global warming over the past 20 years

by Judith Curry

Recent observed global warming is significantly less than that simulated by climate models. This difference might be explained by some combination of errors in external forcing, model response and internal climate variability.

Continue reading

Climate model simulations of the AMO

by Judith Curry

What are the implications of climate model deficiencies in simulating multi-decadal natural internal variability  for IPCC’s climate change detection and attribution arguments?

Continue reading