“Atmospheric rivers” are bringing rain to the frozen slopes of the West Antarctic ice sheet, hitting the ice shelves that play a major role in holding back rapidly retreating glaciers.
In a new study, my colleagues and I show how rain is occurring in sub-zero temperatures due to these “rivers in the sky” – long, narrow plumes of air which transport heat and moisture from the tropics to the mid-latitudes and poles.
Rain in Antarctica is significant, not only because it is a stark indicator of climate change, but because it remains an under-studied phenomenon which could impact ice shelves.
Ice shelves in Antarctica are important gatekeepers of sea level rise.
They act as a buffer for glaciers that flow off the vast ice sheet, slowing the rate at which ice is released into the ocean.
In the study, we explore the causes of rain falling on ice shelves in the Amundsen Sea embayment region, which stand in front of the critically important Thwaites and Pine Island glaciers.
Researchers have warned the collapse of ice shelves in this region could trigger the loss of the entire West Antarctic ice sheet over several centuries.
Rivers in the sky
Atmospheric rivers are typically associated with bringing extreme rainfall to the mid-latitudes, but, in the frigid Antarctic, they can deliver metres of snow in just a few days.
In West Antarctica, atmospheric rivers deliver a disproportionate quantity of the year’s snowfall. Research shows they account for around 13% of annual snowfall totals, despite occurring on just a few days per year.
But what makes atmospheric rivers in Antarctica so interesting is that snow is only part of the story. In extreme cases, they can also bring rain.
To explore how extreme precipitation affects the Amundsen Sea embayment region, we focused on two events associated with atmospheric rivers in 2020. The summer case took place over a week in February and the winter case over six days in June.
We used three regional climate models to simulate the two extreme weather events around the Thwaites and Pine Island ice shelves, then compared the results with snowfall observations.
During both the winter and summer cases, we find that atmospheric rivers dumped tens of metres of snow over the course of a week or so.
Meanwhile, the quantities of rain driven by these events were not insignificant. We observed up to 30mm of rain on parts of the Thwaites ice shelf in summer and up to 9mm in winter.
A mountain to climb
Antarctica’s cold climate and steep, icy topography make it unique. It also makes the region prone to rain in sub-zero temperatures.
The first reason for this is the foehn effect, which is when air forced over a mountain range warms as it descends on the downward slope.
Commonly observed across Antarctica, it is an important cause of melting over ice shelves on the Antarctic peninsula, the northernmost point of the continent.
When air passes over the mountainous terrain of the West Antarctic ice sheet during atmospheric river events, temperatures near the surface of the ice shelves can climb above the melting point of 0C.
This can accentuate the formation of rain and drizzle that stays liquid below 0C – also known as “supercooled drizzle”.
Another factor which leads to liquid drizzle, rather than snow, in sub-zero conditions is a lack of dust and dirt – particles which are usually needed to trigger the formation of ice crystals in clouds.
In the pristine Antarctic, these particles – which act as “ice nuclei” – are few and far between. That means that pure liquid water can exist even when temperatures are below 0C.
The origins of rain over ice shelves
It is easy to assume that rain that reaches the surface in Antarctica is just snow that has melted after falling through a warm layer of air caused by the foehn effect. Indeed, this is what we initially supposed.
But our research shows that more rain reaches the surface of Antarctica when the air near the ground is within a few degrees of freezing.
At times when the foehn effect is strongest, there is often little or no rainfall, because it evaporates before it gets a chance to reach the surface.
However, we saw rain falling well above the warm layer of air near the surface, where temperatures were universally below 0C – and, in some cases, as low as -11C.
Rare rain
Rain in Antarctica is a rare occurrence. The region’s normally frigid temperatures mean that most precipitation over the continent falls as snow.
However, exactly how rare rain is in the region remains relatively unknown, because there are virtually zero measurements of rainfall in Antarctica.
There are a number of reasons for this – rain falls infrequently, and it is very difficult to measure in the hostile Antarctic environment.
Our results show that extreme events such as atmospheric rivers can bring rain. And it is likely that rain will become a more common occurrence in the future as temperatures rise and extreme weather events occur more frequently.
However, until rain starts being measured in Antarctica, scientists will have to rely entirely on models to predict rain, as we did in this research.
It is also not yet known exactly how rain could impact ice in Antarctica.
We do know that rain falling on snow darkens the surface, which can enhance melting, leading to greater ice losses. Meanwhile, rain that refreezes in the snowpack or trickles to the base of the ice can change the way that glaciers flow, impacting the resilience of ice shelves to fracture.
So, if we want to understand the future of the frozen continent, we need to start thinking about rain too. Because while rain may be rare now, it may not be for long.
The post Guest post: How atmospheric rivers are bringing rain to West Antarctica appeared first on Carbon Brief.
Guest post: How atmospheric rivers are bringing rain to West Antarctica
Climate Change
North Carolina Regulators Nix $1.2 Billion Federal Proposal to Dredge Wilmington Harbor
U.S. Army Corps of Engineers failed to explain how it would mitigate environmental harms, including PFAS contamination.
The U.S. Army Corps of Engineers can’t dredge 28 miles of the Wilmington Harbor as planned, after North Carolina environmental regulators determined the billion-dollar proposal would be inconsistent with the state’s coastal management policies.
North Carolina Regulators Nix $1.2 Billion Federal Proposal to Dredge Wilmington Harbor
Australia has some of the largest areas of high volume, consistent solar and wind energy anywhere in the world. It is a natural advantage that many countries in our region and across Europe will envy as they ramp up their efforts to reduce carbon pollution.
Australia has an amazing opportunity to utilise this abundance of reliable energy not only to transform our own energy systems but also that of our neighbours – if we get the policy settings right.
We are, in fact, already seeing the benefits of renewable energy flowing into our electricity grids. With all the inflation pressures on our bank accounts it looks like electricity pricing may be one cost that could be turning a corner – largely thanks to cheap solar and wind energy.
Renewables are Bringing Down the Cost of Producing Electricity
Here at Greenpeace, while we think there are some important questions to ask about renewable energy, it is clear that solar and wind are certainly the cheapest energy options available.
In contrast, coal, oil and gas are not only big on pollution, they are also proving costlier as they struggle to cope with the changing nature of our electricity systems. Plus, fossil fuels are much more exposed to international price fluctuations – as we all experienced when our electricity bills rapidly rose following the Russian invasion of Ukraine.
Wouldn’t it be great if we instead had energy independence, sourced from an infinite supply of clean energy?
Solar and wind (backed by batteries) can do just that and the reality is that they are already out-competing the old guard of gas and coal simply because they are quicker and cheaper to deploy. Which is good news for electricity prices!
Although whether energy retailers are passing on those savings to customers is another question. Short answer: no, they’re not – but it is a bit complex.
Why are my electricity bills still high?
There are a number of elements that make up the final amount we see on our bills. The graph below shows the breakdown of energy costs covered by our bills.
You will see roughly a third (36.2% in 2025-26) of the cost goes to maintenance and build out of the electricity grid. This includes the transmission lines needed to connect to new renewable energy sites and to connect states so they can better share their energy resources. The ‘network’ costs have been increasing but so have other components of our bill, most notably the ‘wholesale’ cost of producing electricity.
Thankfully, the cost of producing the electricity is now starting to go down (thanks to renewables and batteries), but they are coming off record highs thanks to the exorbitant cost of gas and the unreliability of coal power stations that are old and no longer fit for purpose.
During high demand times (eg, when we all get home from work on a hot day and turn on the air conditioning) spot prices can quickly jump. Add to that a couple of coal power plants breaking down (as they increasingly do), and expensive gas fired power use spikes in the system. This can quickly cancel out any of the cost savings solar power may have created during the day when prices can actually go negative.
The good news is that this is exactly the problem batteries can solve. Batteries are great at soaking up the surplus supply of solar during the middle of the day, which creates a more efficient system, and then rapidly pumping out that power during the evening peak at a cheaper rate than gas.
How much have costs come down?
According to the Australian energy regulator (AEMO), wholesale electricity prices across the east coast have dropped by 44% when comparing prices in quarter 4 of 2025 to the same period in 2024.
AEMO directly attributes the change to the significant growth in wind (up 29%), solar (up 15%), and batteries (3,796 MW of new battery capacity added). This influx of cheap renewable energy has seen a corresponding decrease in the use of polluting fossil fuels to power the grid. Coal fired power dropped by 4.6% and gas fired power fell by a staggering 27%.
The same trend can be seen in the world’s largest standalone grid in WA where renewable energy and storage supplied a record 52.4% of the grid’s energy across the final 3 months of 2025. That is an impressive result given there is no interstate connection to borrow energy from and there is no hydroelectric power in the system.
As a result, WA has seen a 13% drop in wholesale electricity prices thanks to a 5.8% reduction in coal fired power and a 16.4% reduction in gas fired power.
Australian Households Lead the Way on Solar and Batteries
Despite all the attempts to discredit clean energy by Trump and other conservative politicians, Aussie households have long known the value of renewable energy. In fact, Australia now holds the title for the highest rate of solar energy per capita in the world.
This is now being followed by the rapid takeup of household batteries with the Clean Energy Regulator being overwhelmed with interest in the Cheaper Home Batteries Program. They now expect to receive “around 175,000 valid battery applications corresponding to a total usable capacity of 3.9 GWh by the end of 2025.”’
All these extra batteries storing the surplus solar energy across our neighbourhoods during the day is not only creating drastic bill reductions for those households who are installing them, it is helping the whole grid. Which eventually will help everyone’s electricity bills.
If Australia as a whole follows the lead of suburban families by switching to cheap solar (plus wind) backed-up by batteries, it has an unparalleled opportunity to build its economy on the back of unlimited, local, clean energy harnessed from the sun and wind.
Powering our Future Economy
If there was ever something Australia has a natural advantage in, its sun and wind. But given the growing demand for electricity from data centres and the electrification of heavy industry, we are going to need more than just rooftop solar panels.
That’s where Australia has the potential, more than almost any other country, to become a renewable energy powerhouse and punch above our weight in the fight against climate change. See for example the unique opportunity to enter into the production and export of green iron.
While there is still quite a way to go before our electricity is fully sourced from solar and wind, we are well on the way. The clean energy charge is gathering pace – and our communities, oceans, wildlife and bank balances will be the better for it.
Climate Change
Whale Entanglements in Fishing Gear Surge Off U.S. West Coast During Marine Heatwaves
New research finds that rising ocean temperatures are shrinking cool-water feeding grounds, pushing humpbacks into gear-heavy waters near shore. Scientists say ocean forecasting tool could help fisheries reduce the risk.
Each spring, humpback whales start to feed off the coast of California and Oregon on dense schools of anchovies, sardines and krill—prey sustained by cool, nutrient-rich water that seasonal winds draw up from the deep ocean.
Whale Entanglements in Fishing Gear Surge Off U.S. West Coast During Marine Heatwaves
-
Greenhouse Gases7 months ago
Guest post: Why China is still building new coal – and when it might stop
-
Climate Change7 months ago
Guest post: Why China is still building new coal – and when it might stop
-
Greenhouse Gases2 years ago嘉宾来稿：满足中国增长的用电需求 光伏加储能“比新建煤电更实惠”
-
Climate Change2 years ago
Bill Discounting Climate Change in Florida’s Energy Policy Awaits DeSantis’ Approval
-
Climate Change2 years ago
Spanish-language misinformation on renewable energy spreads online, report shows
-
Climate Change2 years ago嘉宾来稿：满足中国增长的用电需求 光伏加储能“比新建煤电更实惠”
-
Climate Change Videos2 years ago
The toxic gas flares fuelling Nigeria’s climate change – BBC News
-
Carbon Footprint2 years agoUS SEC’s Climate Disclosure Rules Spur Renewed Interest in Carbon Credits