Can we control glacial melting?
Rising tropospheric Ozone levels, Singapore building nuclear power expertise, UK boosts renewable funding, Robots for installing solar
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Can we control glacial melting?
NOx Emissions are Raising Troposphere Ozone Levels
News from Governments
Top stories
Can we control glacial melting?
In February 2024, EU’s Copernicus Climate Change Service reported that Arctic sea ice was 2% below average, and that little ice remained around Antarctica in the Weddell Sea.
All available research indicates that if greenhouse gas emissions are not reduced significantly, ice sheets both in Greenland and the Antarctic will melt faster and cause sea levels to rise significantly.
Land subsidence due to rising sea levels is already a major concern for coastal cities.
The city of Miami Beach floods on such a predictable basis that if, out of curiosity or sheer perversity, a person wants to she can plan a visit to coincide with an inundation…For the past several years, the daily high-water mark in the Miami area has been racing up at the rate of almost an inch a year, nearly ten times the rate of average global sea-level rise. The New Yorker (2015)
Since action on reducing emissions is proceeding much more slowly than planned, climate scientists and researchers have looked into human interventions to reduce glacial melting.
Here’s a simple idea to understand glacial melting - ice that comes into contact with melted ice (i.e. water), which has more heat energy, is induced to melt. The smaller the block of ice, the more it is affected.
There are small and large ice shelves in the Antarctic waters. Large ice shelves float in water that is at the “sea-surface freezing point” (-1.9℃). These tend to maintain their stability when they encounter the (relatively) warmer ice streams from glaciers which mix with the water on which they float.
Small ice shelves float on what is called “circumpolar deep water” - a mix of water masses from different regions such as North Atlantic, Antarctic bottom water, and Antarctic deep water. These constantly disintegrate and reform, and are likely to melt faster when they come into contact with a warmer ice stream.
Ocean heat content has continuously risen since mid-1990s, closer to the surface at first, and at greater depths of 700-2000m since the early 2000s. This puts small ice shelves at risk.
The melting of smaller ice shelves could “cause several meters of sea level rise in one or more centuries”.
I’m going to make a digression to carbon capture technology here. We discussed Ocean Alkalinity Enhancement (OAE) as a method for carbon dioxide removal a few weeks ago. This involves adding antacids, like Magnesium Hydroxide (MgOH₂), to seawater to cause the oceans to absorb more CO₂. It is believed that doing this will accelerate the carbon cycle in the oceans - carbonates will form faster from the reaction between calcium from alkaline rocks and CO₂. However, more CO₂ in seawater is also likely to increase ocean temperatures.
While current trials of OAE measure local pH, temperature and other metrics near the site of the intervention, the effect of higher levels of dissolved CO₂ on circumpolar deep water are difficult to measure and quantify. Also, the formation of carbonates (into rocks, corals, pearls, shells) is a very long-term phenomena involving both physical/chemical and biological processes. I’m curious if there is research on how long the excess dissolved CO₂, due to OAE or other such interventions, will remain in ocean waters before forming carbonates, and if we know the temporary/permanent impact of this on ocean temperatures.
Back to glacial melting. Researchers are not sure whether making interventions or reducing emissions can counter the effects of emissions already made over the past decades.
If the tipping point into dynamic collapse for parts of the Amundsen Sea sector of the West Antarctic Ice Sheet will soon be, or has already been, crossed, then future emissions scenarios will have little effect on preserving the ice sheet.
Prior research on glacial melting has aimed to answer 2 questions - which physical processes caused loss of ice mass that would raise sea levels, and how climate change affected these processes.
Now scientists are looking to answer 2 more questions -
which natural processes and human interventions can control loss of glaciers,
and what is the “window of opportunity” for implementing these?
One proposed intervention focuses on reducing the circulation of warm circumpolar deep water under the smaller ice shelves. To do this, walls of sediment or fibrous curtains can be set along the seabed.
Another intervention is based on the observation that large amounts of melted water cause the ice in its contact to melt faster, and as this melted ice moves, the heat due to friction between the ice stream and the base further accelerates melting. To counter this, melted ice water may be diverted from the bed of the ice stream to reduce its movement, and eventually let the ice stream freeze. One way to do this is drill holes deep enough to reach the subglacial bed, and remove melted water/heat through these. An advantage of these ‘basal-hydrology interventions’ is their lower ecological impact - since there isn’t much biological life below active ice streams.
There are some other proposals
windbreaks to interrupt blowing snow and increase mass deposition
using cables and anchors to delay rifting and breakup of floating ice shelves
adding reflective materials to the ice surface to reduce ablation
draining melt ponds laterally over the ice sheet surface to prevent their draining downward to the bed
Another proposal is to increase the mass of ice by pumping seawater onto solid ice sheets and letting it freeze in the cooler surface air.
For all of these interventions, little is known about the social, economic and ecological impacts they might have. Such ‘fixes’ may also entirely discourage nations from addressing the core problem - rising global emissions.
In 1990, when the Intergovernmental Panel on Climate Change first assessment report (FAR) was released, global CO2 emissions were 22.8 billion metric tons per year and atmospheric CO2 concentration was 354.5 ppm. Today, the figures are 37.6 billion metric tons per year and 421.9 ppm, respectively. These metrics indicate that the world has done little to slow the emission of CO2 in the 34 years since the first official report of the Intergovernmental Panel on Climate Change.
Do Climate advocates wish to channel funds and human intelligence into interventions that a) may or may not work, b) may cause unknown and unintended effects, while at the same time spending hundreds of billions on flood management?
(Miami alone needs $5 billion to fight flooding)
Glacial Climate Intervention: A Research Vision (PDF)
NOx Emissions are raising (toxic) Troposhere Ozone levels
The naturally-occurring ozone layer is in the stratosphere, about 30 km above the Earth’s surface.
Over the past few decades, countries across the globe have worked together to repair the ozone ‘hole’ over Antarctica by prohibiting use of ozone-depleting substances like flourinated chemicals, as outlined in the Montreal Protocol. An assessment by the United Nations in 2022, found that the interventions seemed to be working and ozone concentration was expected to reach 1980 levels by 2066 in Antarctica, and around 2040 across other regions of the globe.
However, ozone levels are also rising in the upper parts of the troposphere, the layer just below the stratosphere. At this height, ozone does not protect, but rather acts as an air pollutant, contributes to smog, is connected with 1 million premature deaths annually from respiratory illnesses, and about $11-18 billion in crop production losses every year globally.
Analysis of satellite records for 17 years, since 2005, shows rising tropospheric ozone levels.
In-Service Aircraft for a Global Observing System (IAGOS) data indicate increases in tropospheric column O3 of 3.6–18.5% per decade (varying by region) over 1994–2016. Src
While ozone can appear in the troposphere naturally, from exchange with the stratosphere, and from the formation of nitrogen oxides during lighting, the current research shows a clear ‘human fingerprint’ on tropospheric ozone concentration. The primary cause is nitrogen oxides and organic compounds like carbon monoxide and methane, emitted in vehicle exhausts, and from power plants and industrial processes. In the presence of sunlight, these react to form ozone and other compounds.
The team looked through the upper tropospheric ozone data derived from the satellite products, from the years 2005 to 2021, and found that, indeed, they could see the signal of human-caused ozone that their simulations predicted. The signal is especially pronounced over Asia, where industrial activity has risen significantly in recent decades and where abundant sunlight and frequent weather events loft pollution, including ozone and its precursors, to the upper troposphere.
Tropospheric ozone has a strong global warming effect, ranking next only to the effects of CO₂ and methane. It also affects human health, especially the respiratory system, and ecosystems.
MIT News | Anthropogenic Fingerprint Detection in Upper Tropospheric Ozone Trends Retrieved from Satellite
News from Governments
Singapore, currently a nation without any nuclear power, is looking to build technical expertise in the area and has signed an agreement with the US to access their knowledge base on nuclear. ET Energy
The UK has increased its corpus for renewable auctions for this year. The new budget includes £1.1 billion for offshore wind, £185 million for onshore wind and solar, and £270 million for emerging technologies such as floating onshore wind and tidal energy. The maximum strike prices set for auctions in 2024 are:
In this auction the maximum strike price for this auction are as follows:
offshore wind £73/MWh
onshore wind £64/MWh
solar £61/MWh
floating offshore wind £176/MWh
geothermal £157/MWh
tidal £261/MWh
Top Stories
India’s Central Electricity Authority has approved two Pumped Hydro Storage projects with a combined capacity of 2600 MW. Proposals for another 60GW of pumped storage projects are under review. ET Energy
France, Spain and Portugal are collaborating on the H2Med Project that aims to build 703 km of pipelines with a transmission capacity of 2 MTPA (million tonnes per annum) hydrogen by 2030. Offshore Energy
The Geological Survey of India has estimated a potential of 10.6GW geothermal power in India. ET Energy
Maximo, is a robot for installing solar panels, developed by AES.
The Guardian on heat counter-measures at the Paris Olympics. POLITICO reports an average of 175,000 deaths annually from rising temperatures in Europe.
Read about MIT researchers deploying a network of low-cost sensors to collect salinity, temperature, pressure and other data from frozen seas in the Arctic. There are some unique challenges in building these sensors - they need to operate for long periods with low power use, batteries don’t perform well at cold temperatures, and need to be resilient from getting damaged by collisions between large chunks of ice.
A guide to designing a national green hydrogen strategy from IRENA.
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I’m the maker of SummaryWithAI.com. You can find me on Twitter and LinkedIn. I also blog sometimes on Floating Coordinates.
