40 votes
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Does this peer-reviewed study (referenced in Forbes) contradict the accepted position that climate change is real?

I want to know if that article has been refuted anywhere Yes. You can read all about it in the blog post James Taylor misinterprets study by 180 degrees. In short, the original paper was designed ...
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  • 22.2k
25 votes
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Is it true that a butterfly flapping its wings can result in a tornado in a distant location?

The butterfly is a colourful illustration of Chaos Theory, and the word butterfly came from the diagram of the state space (see below). A system that is chaotic is extremely sensitive on its initial ...
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  • 11.1k
17 votes
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How good were climate models of the 1990s at predicting the global temperature trends of the 2000s/2010s?

You might take a look at the Technical Summary of the most recent IPCC Assessment Report (5). Thematic Focus Element #3 is "Comparing Projections from Previous IPCC Assessments with Observations&...
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  • 12.7k
17 votes
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Looking for evidence against some points raised in Ivar Giaever's speech on climate change

Ivar's graph is mischievous in trying to imply that there should be an exact correlation. The global air temperature is not a good parameter to chart against CO2 emissions because the increasing heat ...
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17 votes

Why don't errors accumulate in climate models when the time horizon increases?

Error does accumulate in climate models out into the future -- that's why the forecasts include a range of possible results, that gets wider the further into the future you look. See, for instance, ...
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  • 1,340
16 votes
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"The world will start COOLING DOWN in 2017"?

I gave a longer answer linked to a similar question in the comments above, I'll give a quick one here: There's a story going around the low-grade news factories that one Dr. David Evans . . . ...
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  • 5,707
14 votes

Is it true that a butterfly flapping its wings can result in a tornado in a distant location?

Predictability: Does the flap of a butterfly's wings in Brazil set off a tornado in Texas? That was the title of Edward Lorenz's invited talk at the 139th meeting of the American Association of the ...
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  • 20.2k
13 votes
Accepted

What is the methodology to analyze future climatic extremes using the results of climate models?

Your question is fairly broad, and slightly vague so I don't know if I will be able to answer it in one go. If you would like any clarification, let me know. How are predictions made? The basic ...
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  • 5,327
13 votes
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Looking for the mathematics so I can run climate change simulations

Full scale climate models The atmospheric climate simulations that are presented in the IPCC reports are performed by quite large and complex models. Running these models needs a "supercomputer&...
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12 votes
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What is the predictability of El Niño/La Niña?

All season forecast systems are subject to uncertainty. The uncertainty arises from an imperfect initial state, such as initial conditions, and from imperfect models, such as uncertainty due to, ...
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11 votes

What exactly is a model grid?

A model is a simplified representation of a system. Rather than try to model everything down to the microscopic level, or as vectors, we often aggregate phenomena across geographic areas, to simplify ...
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  • 4,070
11 votes
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What caused peak CO2 to rise, starting about 400,000 years ago?

First things first: There's nothing per se wrong in science with answering "We don't know" to a vexing problem. This might well be one of those cases. The question you are asking was asked by Imbrie ...
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  • 20.2k
10 votes
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Are there any general-purpose climate-model coupling projects?

Yes, there were many model coupling projects in the past, as well as many ongoing coupling projects in the present and near future. The main motivation behind model coupling is the need for the ...
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  • 4,925
10 votes

Are there any general-purpose climate-model coupling projects?

Coupler software (e.g. OASIS, MCT, C-Coupler) is frequently used to combine these different components of earth system models. Of course interfacing models with each other using these couplers or ...
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  • 1,662
10 votes
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How to calculate w-wind?

Omega, ω is closely related to w in meteorology. It can be moved towards w using the chain (this reminder from Watkins at SJSU helped)... ...
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10 votes
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How is global greenhouse gas emission calculated?

Your question is simple enough, but the answer depends on what exactly you're looking for. Who is emitting where right now? Real-time global monitoring of greenhouse gas emissions with a high ...
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  • 11.1k
10 votes

Why don't errors accumulate in climate models when the time horizon increases?

There is a huge confusion between errors in weather forecasting and climate prediction. While weather predictability is fundamentally limited to a few weeks, in climate modelling we are interested in ...
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9 votes
Accepted

How much would the Greenland landmass isostatic rebound contribute to long term climate change?

Be warned this is a general (and speculative) answer, but it was getting too long to be a comment: The bulk of Greenland's ice mass is centred over inland/central Greenland. If you were to take all ...
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  • 1,787
9 votes
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Interpolate Gaussian grids to regular fixed grids using bilinear interpolation?

climate data operators (CDO) define grid We define a lat-lon target grid with 1°x1° grid cell size 30x30 grid cells starting at 40°N and -10°E (=10°W): ...
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9 votes
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How to run earth system, land surface and climate models?

As alluded to in some of the comments, all of the CMIP5 models will have been run on supercomputers, and it takes a lot of effort to get one of them running on a new platform, even for a team who know ...
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  • 3,153
9 votes

How is global greenhouse gas emission calculated?

I can imagine a satellite observation-based model that calculates emissions on a spatial basis but I am not sure if our technology is advanced enough to do that accurately. It is. The first ...
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8 votes

Why has CO2 decreased in the history of the Earth?

The short answer is that most of the Earth's original allotment of CO2 got locked up in various carbonate minerals, largely calcite (limestone, marble, and chalk). According to this article there is ...
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  • 2,137
8 votes

Looking for evidence against some points raised in Ivar Giaever's speech on climate change

Temperature differences y/y are very small compared to natural variation during the year This is only saying that we have a large seasonal cycle. It says nothing about low-frequency variations. Once ...
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  • 101
8 votes
Accepted

Kalman - Data assimilation with external model

$M$ is the forward model you are using. It is the dynamical model used to solve whatever discrete equation evolves the field ($d?/dt=$). The best way to start with data assimilation and understand ...
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  • 14.7k
8 votes
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North Atlantic Oscillation (NAO) future prediction - Academic papers?

A good start is the article by Goodkin et al. (2008) that relates past fluctuations of NAO to climate variability and argues that in the late 20th century NAO changes are much more dramatic as a ...
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  • 14.7k
8 votes
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Confusion with precipitation values in CORDEX MPI-ESM rcp data

TLDR; The precipitation values (and possibly some other variables; see below) need to be divided by 24. Background The global attributes of the netCDF file in the question provide an URL to a ...
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8 votes

Why is a future increase in solar luminosity by 10% supposed to have disastrous consequences for life on earth when the last 30% did not?

In this regard you can think that the Earth system is like a house with heating but no Air conditioning. Therefore, it has a powerful mechanism to stay warm when the solar illumination is weak (...
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8 votes
Accepted

difference between different meteorological models

In general, the relation between the three datasets is as follows: The simulation model is initiated with a set of boundary and initial conditions, and will on the long-term provide good mean ...
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  • 98
7 votes

Why do winter temperatures account for most of the increase in global temperature?

Energy balance in the winter is highly dependent on the total amount of area covered by snow or ice. Snow increases the albedo of the Earth which directs the short-wave radiation from the Sun back ...
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  • 12.7k
7 votes

Looking for evidence against some points raised in Ivar Giaever's speech on climate change

Temperature differences y/y are very small compared to natural variation during the year, and the trend we see could be statistical illusion, especially that the scientists who developed the ...
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