Re: Arctic albedo today
John Nissen
These photos I took a few hours ago near Great Bear Lake, Nunavut, Canadian Arctic, simultaneously show very clearly the albedo differences between Ice, Water, Tundra, Aerosol Haze, and clouds. Albedo change follows melting ice!
From: healthy-planet-...@googlegroups.com <healthy-planet-...@googlegroups.com> on behalf of John Nissen <johnnis...@gmail.com>
Date: Friday, June 12, 2026 at 02:26
To: Jan Umsonst <j.o.u...@gmail.com>
Cc: Bruce Melton -- Austin, Texas <bme...@earthlink.net>, healthy-planet-action-coalition <healthy-planet-...@googlegroups.com>, Robert Chris <robert...@gmail.com>
Subject: Re: [HPAC] State of Carbon Dioxide Removal Report, 2026Thanks Jan,
You say we have the worst case scenario, but presumably you are referring to the carbon cycle and tropospheric aerosols. I think that the accelerated warming, especially in the Arctic, presents the most immediate crisis.
Cooling the Arctic is most urgent because of preventing meltdown while still just possible using SAI. The Arctic and its several tipping elements are close to the point of no return, when disastrous climate change and sea level rise become inevitable.
But we need to pull out all the stops, including SRM and CDR, both to prevent the planet from disastrous climate change and sea level rise in the long-term and to enable climate restoration to late Holocene norms, as our legacy for the future wellbeing of all humanity. What could be more valuable?
All stops includes restoring the cloud cooling from natural aerosols and from anthropogenic SO2. What would you recommend as policy advice for decision makers?
It used to be said that 1/3 of CO2 emissions were absorbed by oceans and 1/6 by plants on land. What are the figures now?
Cheers, John
On Wed, 10 Jun 2026, 1:30 pm Jan Umsonst, <j.o.u...@gmail.com> wrote:
Hi Bruce,
we are in the non-quantifiable worst case now - so many signs that we get a massive carbon feedback already rolling on with a vicious cycle in the oceans now becoming operational. It's like you wrote it - it's not the warming per se, but how the system responds and it seems to be much more sensitive to GHG changes than we thought - several discussions/observations emerge now which really do not look good...
I found it surprising that the sink numbers are so heavily discussed - the terrestrial carbon sink could be way weaker than modeled this would make the oceans the main sink - but all not certain but recently a new paper came out substantiating the weaker terrestrial carbon sink position - some 0.6 Gt C if I'm not mistaken - let's see how it will further evolve the discussion.
With ulrafine aerosols you are also spot on - they go up, likely steeply in a warmer climate - extreme weather pushes particle formation - oops!
The discussion is starting since some years - fossil fuel ultra fine aerosol emissions could have doubled the last decades - unfortunately the intricacies are often overlooked in the SOx cooling debate. Ultra fine aerosols are very effective at creating cloud nucleus (later I copied & pasted where our knowledge stands). Hence, it's not just about the SOx total emissions numbers but also composition changes...
Here what they write on the increase in ultrafine particles:
Ultrafine particles (UFP) acting as cloud condensation nuclei (CCN) are the driving force behind changing rainfall patterns. Recently observed weather extremes like floods and drought might be due to changing anthropogenic UFP emissions. However, the sources and budgets of anthropogenic primary and secondary particles are not well known. Based on airborne measurements we identified as a major contribution modern fossil fuel flue gas cleaning techniques to cause a doubling of global primary UFP number emissions. The subsequent enhancement of CCN numbers has several side effects. It’s changing the size of the cloud droplets and delays raindrop formation, suppressing certain types of rainfall and increasing the residence time of water vapour in the atmosphere. This additional latent energy reservoir is directly available for invigoration of rainfall extremes. Additionally it’s a further contribution to the column density of water vapour as a greenhouse gas and important for the infrared radiation budget. The localized but ubiquitous fossil fuel related UFP emissions and their role in the hydrological cycle, may thus contribute to regional or continental climate trends, such as increasing drought and flooding, observed within recent decades. " Unprecedented levels of ultrafine particles, major sources, and the hydrological cycle"; https://www.nature.com/articles/s41598-022-11500-5
This is highly relevant:
"increasing drought and flooding" - the former leads to hot and dry conditions under which clouds vanish while the later produces heat that fuels heatwaves.
Here you have the cloud condensation nuclei effects of UFP's from a recent review on the matter:
NFP - new particle formation
Climate modulation
The interactions of UFP with other members of the climate system are complex (Fig. 6). UFP can reflect, scatter and absorb solar radiation (Luo et al., 2019; McFiggans et al., 2004; Peng et al., 2002). Some studies have pointed out that BC constitutes a considerable part of UFPs, which can strongly absorb electromagnetic radiation in the visible and infrared spectra, thereby affecting global warming (Bond et al., 2013).
The simulation results of aerosol radiative forcing based on numerical model show that the aerosol radiative forcing significantly increases when nucleation process is considered (Makkonen et al., 2012). Meanwhile, solar radiation directly affects radiation-dominated NPF events, which further affects the number of UFP in the atmosphere (Brines et al., 2015; Lee et al., 2003). As the climate warms, the occurrence of extreme events will also enhance various plant stressors, which will affect NPF events by affecting the emission of precursors (Zhao et al., 2017).
The emissions of UFP may affect cloud property changes to further alter rainfall patterns, which may lead to uneven regional precipitation, thereby increasing the frequency and intensity of extreme weather events and leading to significant natural disaster losses (Facchini et al., 1999; Junkermann and Hacker, 2022; Junkermann et al., 2011; Kwon et al., 2020). This process is a kind of indirect climate effect of aerosols. Because reproducing the various environmental elements involved in aerosol-cloud interactions is hard, it's difficult to derive a clear causality for the hydrological cycle. The precipitation can accelerate the wet deposition of particulate matter. While clouds increase water mist-dominated NPF events, affecting the amount of UFP in the atmosphere.
NPF is a major source of global tropospheric total particle number concentration and an important contributor to the cloud condensation nuclei (CCN) budget (Bangert et al., 2013; Fan et al., 2018; Jathar et al., 2020; Junkermann and Hacker, 2022; Kerminen et al., 2018; Kwon et al., 2020; Lee et al., 2003; Nair et al., 2020; Pierce and Adams, 2007; Yin et al., 2022). In the general atmosphere, the ability of particles to become CCN is largely determined by aerosol particle size rather than composition (Dusek et al., 2006).
In terms of aerosol particle size, particulate matter with a diameter of about 50–150 nm can directly participate in cloud droplet activation and particles smaller than 50 nm can be activated at unusually high water vapor saturation ratios such as when located in a deep convective cloud system (Kerminen et al., 2012, 2018). Whether UFP can grow into CCN depends on the ability of the particle to grow rapidly into the CCN size range (Johnston et al., 2013). The growth rate of the particle must exceed the loss rate due to clearance in order for the particle to reach the size range of the CCN (Pennington et al., 2013; Westervelt et al., 2014). In terms of chemical composition, normally, the particles in the atmosphere are mainly a mixture of secondary inorganic ions and organic matter. In different regions, the total concentration and proportion of particulate matter are different, but on the whole, the crystal structure is not different, and the influence on becoming a condensation nucleus is not very big. While in the case of artificial rainfall, chemical composition is more important than particle size. The role of silver iodide catalysts in artificial rainfall was taken as an example. As the most widely used catalyst in weather modification field experiments and operations, the hexagonal structure of AgI is similar to that of natural ice crystals (Lou et al., 2021). Due to its special crystal structure, silver iodide is far more likely to become ice core than other substances, and has a more significant effect on CCN (Lou et al., 2021).
Source: "Review on main sources and impacts of urban ultrafine particles: Traffic emissions, nucleation, and climate modulation"; https://www.sciencedirect.com/science/article/pii/S2590162123000217?via%3Dihub
Hence, in terms of the net aerosol cooling effect of the whole composition because of reduced SOx emissions nothing is certain. New results leaving likely out UFP's even see no net radiative effect of aerosol concentration changes - Northern Hemisphere they decrease while in the Southern Hemisphere they increased - but here exists a dataset problem - so not clear yet how robust.
Best
Jan
On 6/10/26 17:33, Bruce Melton -- Austin, Texas wrote:
the biggest probably being that the amount of warming doesn't matter - it's the responses that count.
--Jan UmsonstWallauer Str. 6D, 30326 Frankfurt am MainTele: 0176 41114523E-Mail: j.o.u...@gmail.comPerforming Vitality: https://performingvitality.wordpress.com/--
You received this message because you are subscribed to the Google Groups "Healthy Planet Action Coalition (HPAC)" group.
To unsubscribe from this group and stop receiving emails from it, send an email to healthy-planet-action...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/healthy-planet-action-coalition/CACS_FxqOXdeZUXd7EqdcTNGiBYRKc8i_5SPqbMVE5vo1QQmtTA%40mail.gmail.com.
