Welcome to another edition of Climatebase Weekly (Thursday, October 9th, 2025).

In today’s edition…

🌟 Featured climate jobs at 15+ new employers — Scroll down to view them all!

💼 Register for Climatebase LIVE — The world’s largest online climate career fair.

🌎 The Undercurrent: The Debate Over Geoengineering and Climate Change.

Quick reminders:

​​Climatebase LIVE is a virtual career fair series by Climatebase, designed to help you learn about climate organizations that are actively hiring.

​🏢 Kestrix: Kestrix is A ClimateTech / PropTech startup on a mission to accelerate the retrofit of existing buildings with better data.

⚡Nira Energy: Nira Energy is equipping transmission planning teams and project developers with transparent, ISO-accurate tools to de-risk interconnection and enable efficient grid transformation.

🌘 Five Moon Technologies: Five Moon empowers renters to go electric. They deliver affordable EV charging for renters now, while laying the foundation for backup power and energy independence – so that when the grid goes down, renters aren’t left in the dark.

☀️ Greentech Renewables: Greentech Renewables is a solar distribution company with over 100 locations across the US.

🤝 PowerHouse Texas: PowerHouse Texas (501c3) equips Texas energy policy leaders with evidence-based, bipartisan education through programs such as the Policy Fellowship, Energy Policy Advisory Council, Texas Energy Tour, Innovation Forums, and Energy Academy.

📊 Nettie: ​Nettie is an AI-powered ESG reporting automation platform that transforms financial and sustainability data into auditable regulatory reports aligned with global standards (IFRS S1/S2, EU Taxonomy, Brazilian regulations), designed to make compliance a competitive advantage rather than a cost burden.

Degrees: Real talk about planet-saving careers just launched a new podcast miniseries, Connection as a Climate Solution, in collaboration with Environmental Defense Fund and OpenDoorClimate. The series explores how relationships unlock climate careers and action — with real stories, practical advice, and weekly opportunities to connect live with the hosts, guests, and fellow listeners. Learn more and start listening here.

🎧 Series trailer: Connection as a Climate Solution

By Abigail Bassett 

Geoengineering has been in the news lately, from politically charged rhetoric over cloud seeding to scientific debates over whether climate change already requires dramatic interventions. 

Most recently, geoengineering garnered attention from the scientific community when a small U.K. startup tested a controversial method of refreezing Arctic sea ice by pumping seawater onto the surface, with the goal of thickening the melting ice sheet. The experiment’s aim is to restore the Arctic’s reflective “mirror” effect that helps cool the planet. Putting aside the politicization of geoengineering that has occurred over the last few years, the experiment has, remarkably, sparked fierce debate within the scientific community. 

Here’s what you need to know about the latest conversations around geoengineering and what it could mean for climate change. 

As global temperatures continue to rise, the once-taboo concept of geoengineering has entered serious scientific and policy conversations.

In simple terms, geoengineering is a series of deliberate, large-scale interventions in Earth’s climate system to offset the effects of global warming. There are two main approaches to geoengineering: carbon dioxide removal (known as CDR) and solar radiation management (known as SRM).   

The latter of these has proven to be the more controversial. The goal of SRM is to reflect a small portion of sunlight back into space using aerosols or cloud brightening to temporarily cool the planet. Research into the physical and chemical processes underlying SRM is still ongoing, while researchers in the UK have begun field deployments to test a technology whose ethical merits and repercussions are still being debated in academic circles.   

The human desire to control weather and climate goes back centuries. Post-World War II cloud-seeding experiments in the U.S. marked the first large-scale attempts. But the idea of deliberately rebalancing Earth’s energy system didn’t gain traction until the 2000s, when Nobel laureate Paul Crutzen argued that we might one day need to inject reflective particles into the stratosphere to avoid climate catastrophe.

Since then, research programs at Harvard (which were stopped in 2024) and elsewhere have modeled potential outcomes, while small-scale field trials—like proposed aerosol or marine-cloud experiments—have sparked protests and regulatory pushback. Supporters argue that geoengineering could buy time if global mitigation efforts fail, while critics contend that it is a dangerous distraction that risks destabilizing weather patterns, exacerbating inequities, or creating a moral hazard.

No global governance system currently exists to regulate these technologies. Treaties like the 1977 Environmental Modification Convention ban hostile use of climate modification, but not peaceful research. Geoengineering currently sits at the intersection of scientific curiosity and planetary hubris, and things are beginning to heat up. 

At the center of the ice experiment controversy is a fundamental clash over unknown risk, responsibility, and reality. The question is whether humans should try to deliberately manipulate the planet’s climate systems to counter global warming or whether doing so risks worsening the very crisis it's trying to solve. 

Proponents of the ice experiment argue that it is essentially SRM-adjacent, since the aim is to increase the reflectivity of the ice, rather than directly reflecting sunlight high in the atmosphere. While that may seem like splitting hairs, it's an important distinction. Proponents of the experiment argue that the rapid loss of Arctic ice is creating a planetary emergency that demands immediate response. They view geoengineering, like the ice experiment, as a potential stopgap to buy time while emissions are reduced. 

Critics have pushed back on the plan with concerns on all fronts, arguing that these kinds of interventions won't scale, are scientifically uncertain, politically ungovernable (if the ratification of the High Seas Treaty is any indicator), and ethically fraught. Critics argue that the experiment is unlikely to scale to the size of the Arctic and warn of unintended ecological risks, including changes to marine habitats and unforeseen effects on ocean circulation. Some climatologists caution that this kind of intervention could backfire or merely buy time at a huge cost. 

Meanwhile, Indigenous and Arctic communities have raised questions about justice and respect for their sovereignty concerns: several argue the project lacks free, prior, and informed consent, and characterize it as techno-colonialism — a way for outsiders to intervene in lands and waters without accountability. 

A new review published in Frontiers in Science, co-authored by 42 scientists, assessed five polar geoengineering strategies: stratospheric aerosol injection, sea ice thickening, sea curtains, glacier basal water removal, and ocean fertilization. All five were found to be either “not feasible” or “environmentally dangerous,” leading the authors to call for an end to further research in these areas. The authors argued that the proposals fail under multiple dimensions — effectiveness, cost, governance, negative side effects, and scalability. They warned of “termination shock” (a rapid rebound in warming if an intervention stops), ozone damage, and the danger of diverting time and resources away from proven mitigation strategies.

That article, however, triggered pushback that technical flaws don't justify shutting down all research into climate interventions. An open letter from 88 scientists responded by dismissing the idea that the reviewed paper reflects a true scientific consensus against geoengineering research. 

This all underscores just how fraught, interrelated, and complex climate solutions can become when ethical concerns run into high expectations based on still-emerging science.

 Proponents of continued geoengineering research argue that as ice melts, fires intensify, and temperature records continue to fall, the world cannot afford to ignore any potential tools. Critics argue that the allure of technological escape risks paralyzing the real action needed to reduce global greenhouse gases, offering the illusion of control in a world that's increasingly pushed past the brink of no return in the climate crisis. 

Both make defensible points: Geoengineering is not a replacement for decarbonization, but it could be a tool to stave off further catastrophe. The more difficult challenge lies in how we choose to govern and manage such a powerful tool, and how we decide what risks are acceptable, which communities have (or don’t have) a voice, and ensure that desperation doesn't become a free license for planetary experimentation. 

Check out some of the latest featured jobs below. If you don't see anything that speaks to you, you can always go to Climatebase to explore over 50,000 new climate jobs.

AZX, PBC.

“AI Transformation Engineering”

Planetary Scale

“We partner with climate-focused founders and early-stage leadership teams to increase access to capital, accelerate growth, and de-risk the pathway to massive impact.”

Carbonfuture

“"Building trust infrastructure to scale durable carbon removal for a sustainable, net-zero future."”

Nira Energy

“Accelerating 100% fossil-free power grid by optimizing renewable energy site selection.”

Spark Climate Solutions

“Innovative nonprofit mitigating climate risk through methane reduction and Earth systems management.”

Electric Hydrogen

“Affordable decarbonization solutions for major industrial sectors, tackling climate change with urgency.”

Euclid Power

“Driving renewable energy projects with advanced data management and workflow tools.”

Crusoe

“Transforming stranded energy into eco-friendly power for data centers, reducing environmental impact significantly.”

Thalo Labs

“Revolutionizing real-time greenhouse gas reduction for buildings with advanced sensing, software, and capture technology.”

SMA America

“Empowering global energy independence for a sustainable, climate-friendly future.”

Seabound

“Carbon capture tech for ships, reducing exhaust CO2 by up to 95%.”

Peak Energy

“Pioneering American company advancing global Sodium-Ion battery systems for renewable energy storage and grids.”