Exxon and AGU Funding

... forgive us Father IF we have sinned?

Background

This note prompted by today's post by Prof. Rabett:

Contrary to the wisdom of many, continents do shift slowly with time, and learned societies do listen to the membership.  Recently a number of members (some very prominent, others not) wrote to the American Geophysical Union asking that the AGU divorce itself from Exxon sponsorship.

This was motivated by a series of articles which exposed Exxon's sponsorship of crank tanks opposing action on climate change, indeed, rejecting the idea that humans are driving climate change in ways that are not so good for the inhabitants, people and other critters.

Eli then quotes part of a letter he received from the Executive Director of the AGU:

In addition to comments on the post itself, over the past three weeks we have received more than 100 emails, letters and phone calls, and countless tweets and comments on Facebook. And the letter referenced in the post, which calls for AGU to sever our relationship with Exxon, has since received additional signatures, growing from 71 AGU members and 33 non-members, to 136 members and 81 non-members (as of 15 March).

This feedback, from AGU members and others in our community and beyond, expressed a wide variety of views, ranging from requests to completely sever the relationship immediately to suggestions for how the relationship could be expanded and made more productive to the view that severing the relationship would violate our scientific integrity. While the social media posts and public comments have tended to be one-sided, the emails received directly from members have been more nuanced and diverse in views expressed. A major theme that emerged is a strong desire among our members to see this issue is treated thoughtfully and with integrity, and to ensure that our discussions be representative of all sides of AGU’s community.

All links in original.

Gas in a Closed System Part 1

... does it maintain a temperature gradient after it comes to rest?

Background

As an extension of the conversation on the Competing Mechanism thread, Chic and I have been swapping e-mails behind the scenes.  Over the course of the exchanges, some thought experiments have been proposed which I think warrant an article of their own, and Chic has given me permission to publish whatever portions of our private communications as grist for that mill.

As some of these thought experiments get quite long, this will be a multi-part series.  First thought experiment is an actual experiment ...

PG&E's Solar Choice Program

... does it make sense?

Background

I'll let Wikipedia do the first part of the intro for me:

The Pacific Gas and Electric Company, commonly known as PG&E, is an investor-owned utility that provides natural gas and electricity to most of the northern two-thirds of California, from Bakersfield almost to the Oregon border. It is the leading subsidiary of the PG&E Corporation.

PG&E was founded in 1905 and is currently headquartered in the Pacific Gas & Electric Building in San Francisco.

It's major "competitors" are Southern California Edison and San Diego Gas & Electric.  Scare quotes because, like many public utilities, PG&E and its cohorts have had virtual monopolies in the regions they serve.  Being investor-owned (publicly traded on the NYSE, ticker = PGE) and not publicly owned, it not surprisingly has a history of dubiously taking advantage of California's ballot initiative system to maximize shareholder value at the expense of its customers' choices and pocketbooks.

The Difference Between Fraud and Farce

... because apparently some people don't recognize the difference.

Update 3/24/2016

Since writing this post, I have reversed my position on the reliablilty of Cook (2013).  The short version is that I no longer stand by its methods and don't have high confidence in its conclusions.  The long version may be found here.

Background

Much has already been written about Cook et al. (2013), Quantifying the consensus on anthropogenic global warming in the scientific literature, so a brief summary should suffice.  Taken directly from the abstract, the salient findings are:

Abstract

We analyze the evolution of the scientific consensus on anthropogenic global warming (AGW) in the peer-reviewed scientific literature, examining 11 944 climate abstracts from 1991–2011 matching the topics ‘global climate change’ or ‘global warming’. We find that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming. Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global warming. In a second phase of this study, we invited authors to rate their own papers. Compared to abstract ratings, a smaller percentage of self-rated papers expressed no position on AGW (35.5%). Among self-rated papers expressing a position on AGW, 97.2% endorsed the consensus. For both abstract ratings and authors’ self-ratings, the percentage of endorsements among papers expressing a position on AGW marginally increased over time. Our analysis indicates that the number of papers rejecting the consensus on AGW is a vanishingly small proportion of the published research.

My bold added, because it's the source of much consternation.  Unpacking those particular statistics gives this expanded tally:

 62.7% support AGW
 35.5% no position
  1.8% reject AGW
------
100.0% total

Lapse Rate on Venus, Part 2

Review of Part 1

In the first post of this series I made two plots which warrant being shown sequentially without any intervening verbosity:

Figure 1 - Observed and (simplistically) modelled temperature profiles of Venus from the surface to 150 km altitude.

Figure 2 - Calculated blackbody radiant fluxes of the temperature curves shown in Figure 1.

As I see it, some takeaways from Figure 1 are:

1. The dry adiabatic lapse rate as modelled by -g/Cp explains most of the observed temperature profile up to 60 km with reasonable fidelity.
2. Extending the lapse rate curve much past 80 km altitude results in a physically ridiculous negative absolute temperature prediction and ..
3. ... it's obviously inconsistent with observation above 60 km.
4. As drawn, the dry adiabatic lapse rate curve intercepting observation at (261 K, 60 km) predicts a surface temperature of 887 K, or 148 K higher than the observed value.
5. According to some class notes I obtained from a quick Google session, dry adiabatic lapse rate should be less than observed lapse rate in a convective atmospheric regime.  In Part 1 I goofed: the other way of saying this is that when actual absolute temperature is greater than what -g/Cp would predict, the atmosphere is destabilized from below by the relative buoyancy of the warmer air, and convection is the result.
6. Above 60 km, stuff happens which -g/Cp cannot explain, but neither should it be ignored.

Point (5), being an egregious error on my part, needs to be sorted first ...

Lapse Rate on Venus, Part 1

... does it explain why the surface is so hot?

Background

One ... occupational hazard ... of invoking Venus as the Solar System's poster-child example of (runaway) CO2-induced global warming is that some folks (properly) don't take the proposed mechanism of its lead-melting surface temperature lying down.  Sometimes, they even raise (annoyingly) good questions.  Here's Chic Bowdrie from a comment in the Competing Mechanisms article:

The surface of Venus is 740K. The temperature is 310K at 53 km. That makes the lapse rate 8.2 K/km. This is pretty close to a value of 7.4 K/km calculated from g/Cp using 8.87 g/sec2 for the gravity on Venus and 1.2 J/g-K for the heat capacity of CO2. Radiative forcing is not required to explain the temperature profile of Venus.

 A visual may be of some help:

Figure 1 - Temperature profiles for Mars, Earth and Venus taken from Astronomy Notes by Nick Strobel.

MODTRAN Radiative Atmospheric Model Part 1

Introduction

MODTRAN is a spectral band radiative transfer code first developed in the late 1980s by Spectral Sciences, Inc. in partnership with Air Force Geophysics Laboratories.  It was essentially a higher resolution (1.0 cm-1) version of AFGL's LOWTRAN code which integrated radiation transfers over 20 cm-1 wavebands.

The most recent version, 5.2, was released in 2009 and is proprietary.  A single license runs $1200, technical support and updates are extra.  Too rich for this hacker.

Older versions are in the public domain with the full FORTRAN source code available for anyone to download, compile, and execute on a local machine.  Too much hacking for this poseur.

Some smart folks at U. of Chicago have been kind enough to host a web-enabled copy of MODTRAN3 Version 1.3 12/1/95, which sports a simple and mostly intuitive GUI and outputs some pretty pictures:

Figure 1 - The graphical output for a model run with default options set.  Isn't it purty?