Subject: RE: [geo] Amine cloud brightening

Hello All,

A few comments following on from the valuable ones
made by Adrian Tuck:-

The production of water clouds in the atmosphere requires more
than effective cloud condensation nuclei, CCN.

The atmosphere needs to be unstable, so that ascent of moist air, once
initiated, will continue, the air will cool [because of expansion
resulting from the reduced pressure] so the relative humidity increases.
When it reaches 100% condensation occurs on suitable CCN, forming droplets
which grow as they rise in the supersaturated environment of thewater clouds.

The presence or absence of such clouds in a given region is much more likely
to be governed by the meteorology, particularly the stability issue - as
above - than by the presence or absence of suitable CCN. Suitable CCN
required for droplet formation are almost always present in the natural

The Marine Cloud Brightening MCB idea, first published in Nature in 1990,
and followed by about 15-20 more detailed articles, involves generating
seawater droplets - of specified, controllable flux and size - which are
very effective as CCN. In my view, this is a much more reliable and
promising way of enhancing the albedos of marine stratocumulus clouds,
to produce a global cooling.

Best wishes, John Latham.

John Latham
Address: P.O. Box 3000,MMM,NCAR,Boulder,CO 80307-3000
Email: [email protected] or [email protected]
Tel: (US-Work) 303-497-8182 or (US-Home) 303-444-2429
or (US-Cell) 303-882-0724 or (UK) 01928-730-002
From: [email protected] [[email protected]] on
behalf of Dr. Adrian Tuck [[email protected]]
Sent: 17 October 2013 13:19
To: Andrew Lockley
Cc: geoengineering
Subject: Re: [geo] Amine cloud brightening

Not a new idea. Also, the reality is that cloud formation in the atmosphere
will always involve a chemically complex mixture: Murphy, Thomson & Mahoney,
Science, 282, 1664-1669 (1998) detected 46 different elements with a single
particle technique (Particle Analysis by Laser Mass Spectrometry) in a million
or so particles during 5 6 aircraft flights, with up to 10 elements in some
particles. For proteinaceous material, see:-

Author(s): MILNE,
Source: JOURNAL OF ATMOSPHERIC CHEMISTRY Volume: 16 Issue: 4 Pages:
361-398 DOI: 10.1007/BF01032631 Published: MAY 1993
Times Cited:
(from Web of Science)
Cited References:
[ view related
] [Citation Map] Citation Map
Abstract: The presence of amino acids in atmospheric precipitation and aerosols
has been noted for many years, yet relatively little is known about these or
other nitrogen containing organic compounds in the atmosphere. Marine and
continental rainwater analyses indicate that atmospheric aerosols, and
subsequently atmospheric precipitation, may contain substantial levels of free
and combined amino acids. The most likely source of amino N in the remote
marine atmosphere appears to be the injection of proteinaceous material through
the action of bursting bubbles at the sea-air interface or the long range
transport from terrestrial sources. The capacity of these substrates to undergo
photooxidation and photodegradation in the atmosphere to simpler species, such
as ammonium ions, carboxylic acids, and for the S containing amino acids,
oxidized forms of sulfur, has received little attention from atmospheric
chemists. The photochemistry of covalently bound amino groups, particularly as
found in peptides and amino acids, is discussed here with the purpose of
summarizing what is known of their occurrence and their possible importance to
atmospheric chemistry.
Accession Number: WOS:A1993LB83200005
Document Type: Review
Language: English
Reprint Address: MILNE, PJ (reprint author)

Web of Science Categories: Environmental Sciences; Meteorology & Atmospheric
Research Areas: Environmental Sciences & Ecology; Meteorology & Atmospheric
IDS Number: LB832
ISSN: 0167-7764

On 17 October 2013 12:56, Andrew Lockley
<[email protected]<mailto:[email protected]>> wrote:

Poster's note : appears off topic, but later discusses how amine release could
be used for geoengineering purposes

Original paper at

Cloudy with a chance of... climate change: Discovery that agricultural
practices help form clouds could change the way we calculate global warming -
Climate Change - Environment - The Independent

A team of scientists led by a British academic has solved a long-standing
enigma to explain how up to half the clouds in the sky are formed. And in
finally cracking the problem of how planet-cooling clouds are conjured from
what might seem to be thin air, the researchers found that humans play a
significant role. It is a discovery that could fundamentally change our
understanding of climate change, and may even mean experts have underestimated
just how warm the planet will get over the next century.

The mystery was that many clouds appeared in the sky even though there were no
"seeds" – often just specks of dust – that must be present for water droplets
to form in the air. But, writing in the journal Nature last week, researchers
from the Cern laboratory in Switzerland described for the first time how a
chemical soup of gas vapours can react to form the necessary tiny particles.To
do so they had to build a chamber of "unprecedented cleanliness" at Cern in
order to ensure they could work out exactly what was going on in the
atmosphere."This is the first time that atmospheric particle formation has been
reproduced with complete knowledge of the participating molecules," said
Professor Jasper Kirkby, leader of the research team. "This is an important
step forward, but we still have a long way to go before we fully understand the
processes of aerosol formation and their effects on clouds and climate."The
research showed that gases called amines – produced in large quantities as a
result of farming cattle and other animals – can help form the seed particles
when combined with sulphuric acid in the air. Breathe in air from a farm and it
is likely you are getting a lungful of amines, as they come from the breakdown
of proteins and can be found in animal slurry. Rotting fish gives off a
particularly concentrated dose.Professor Kirkby, originally from Manchester,
stressed it was possible that clouds could be produced in a similar way with
sulphuric acid but with different kinds of vapours than amines. He said this
newly discovered process would have to be factored into climate change models
used by the Intergovernmental Panel on Climate Change (IPCC).The lack of
knowledge about aerosols – particles suspended in the atmosphere – and their
effect on clouds is widely recognised as the major source of uncertainty in
predictions about global warming. "We have to understand how clouds have been
changed by human activity or natural activity if we are to understand climate
change in the 20th century and therefore have reliable projections in the 21st
century," Professor Kirkby said.The global average temperature on land and sea
rose by 0.85C from 1880 to 2012, the IPCC said in a major report last month.
The fact that amines are produced by animal husbandry means that humans are
responsible for a previously unknown cooling effect on the planet. So the
overall man-made "forcing" of the climate – once greenhouse gases are taken
into account – may actually be less than thought.And that could be bad news
because, Professor Kirkby said, it suggested "the climate may be more sensitive
than previously thought". "If there's been more cooling from aerosols than
thought at the moment then this temperature rise will have resulted from a
smaller forcing – or change – than previously thought," he said. "That would
mean the projected temperatures this century for a doubling of carbon dioxide
may be bigger than current estimates."In its report the IPCC said that
temperatures could increase by between 0.6C and 4C by 2100 depending on carbon
emissions. The latter figure would cause sea levels to rise substantially and
increase the frequency of storms, droughts and other hazardous weather. A
temperature rise of more than 2C above pre-industrial levels is seen as the
point at which the effects become dangerous.The study suggests a possible way
scientists could create clouds to help cool the Earth, although such
geo-engineering is controversial. Amines are also used in carbon-capture at
power stations and factories, so this might be a spin-off benefit.Gerald North,
professor of atmospheric sciences and oceanography at Texas A&M University in
the US, welcomed the research, saying that aerosols had been "really very
poorly understood". He described the idea that climate models may have been
underestimating global warming over the next century as "very interesting", but
also warned of the need for more research on the subject.Professor North
suggested the discovery might offer some form of hope for the planet. "We don't
know if these amines are increasing the same way that carbon dioxide is
increasing," he said."If they were increasing at the same rate, maybe
everything would be fine! But we don't know."Piers Forster, professor of
physical climate change at Leeds University, said people had previously tried
to work out the cloud-making process, speculating about ammonia, cosmic rays
and other factors."If you get amines being produced in parts of the world that
are very pristine, this could have a direct effect on clouds," he said. While
the research would help improve climate models, he said he doubted it would
alter temperature projections significantly.

You received this message because you are subscribed to the Google Groups
"geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email
[email protected]<mailto:[email protected]>.
To post to this group, send email to
[email protected]<mailto:[email protected]>.
Visit this group at
For more options, visit


'ATMOSPHERIC TURBULENCE: A Molecular Dynamics Perspective'.
Oxford University Press, 2008. ISBN 978-0-19-923653-4.


You received this message because you are subscribed to the Google Groups
"geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected]
To post to this group, send email to [email protected]
Visit this group at
For more options, visit

You received this message because you are subscribed to the Google Groups
"geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected]
To post to this group, send email to [email protected]
Visit this group at
For more options, visit

Programming list archiving by: Enterprise Git Hosting