How to Reduce the Climate Impact of Your Investments

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Understand your portfolio's performance and its climate impact in one place — then improve both.

Most investing platforms tell you what your portfolio is worth. Ziggma also tells you what it costs the planet, and gives you the tools to change that. In a few minutes, you can measure your portfolio's climate footprint, find lower-impact alternatives, and rebuild around holdings that align with the world you want to invest in. Learn what climate impact means for your portfolio.

Start by measuring your climate impact

When you connect a portfolio in Ziggma, you'll see a metric we call Global Warming Potential, expressed in degrees Celsius — for example, 1.92 °C or 2.28 °C.

A quick note on the name, because precision matters when you're making decisions with your money: what we display is technically an Implied Temperature Rise (ITR). It's an estimate of how much global warming the world would experience by 2100 if the entire economy operated like the companies in your portfolio, relative to their stated emissions pathways and science-based benchmarks.

"Global Warming Potential" in formal climate science refers to something different — it's a coefficient used to compare the warming effect of different greenhouse gases (methane vs. CO₂, for instance). We use the more intuitive label in the app because it communicates the idea faster to investors who aren't climate scientists. But under the hood, the number you see is ITR, and it answers a question every climate-aware investor should be asking: is my money pulling the planet toward 1.5 °C, 2 °C, or 3 °C?

Ziggma doesn't currently compute a portfolio-level carbon footprint (tonnes of CO₂e). ITR is, for most investors, the more actionable signal: it's forward-looking, it incorporates company commitments and trajectories, and it maps directly onto the Paris Agreement targets you already know.

Mobile view of a stock's Climate Action score, showing Global Warming Potential of 1.3 °C, Carbon Intensity, and Carbon Intensity Change as the underlying components.

What the temperature numbers actually mean

Implied Temperature Rise maps your portfolio onto the same scale climate scientists use to describe global warming pathways. A quick reference:

1.5 °C — Aligned with the Paris Agreement's most ambitious target. Limits the most severe climate impacts. Few diversified portfolios sit here today without deliberate construction.

Below 2.0 °C — Aligned with the Paris Agreement's headline goal. Significant climate disruption but within bounds most scientists consider manageable.

2.0–2.7 °C — Where most diversified equity portfolios sit today. Above the Paris targets but below worst-case scenarios.

Above 3.0 °C — Trajectory associated with severe, compounding climate impacts. Often signals heavy exposure to fossil fuel production or high-emitting industrials without credible transition plans.

Bringing your portfolio's number down doesn't require divesting from entire sectors. It typically means selecting the companies within each sector that have credible decarbonization commitments and are already shifting their energy mix.

Reference scale showing what different Implied Temperature Rise values mean for an investment portfolio: 1.5 °C aligned with the Paris Agreement's most ambitious target, below 2 °C aligned with the Paris headline goal, 2.0–2.7 °C where most diversified portfolios sit today, and above 3 °C indicating a high-warming trajectory.

S&P 500 Implied Temperature Rise per Ziggma data as of May 2026. Published estimates from other providers vary based on methodology.

Why most investing platforms don't show you this

If you've never seen an Implied Temperature Rise figure for your portfolio before, there's a reason. Climate data at this level — company-by-company temperature alignment, carbon intensity trajectories, renewable energy mix, controversy tracking — has historically lived inside Bloomberg terminals and institutional research subscriptions costing thousands per seat.

Most retail brokerages don't display it. Most robo-advisors abstract it away inside a single ESG score. Most "sustainable investing" apps either lock you into pre-built thematic portfolios or stop at fund-level labels that obscure what you actually own.A handful of platforms have started bringing this data to self-directed investors, with different tradeoffs in coverage, depth, and how much control you keep over your portfolio.

We've compared them side by side:The best platforms for climate-aligned investing in 2026.

How to lower your portfolio's temperature on Ziggma

Knowing the climate impact of your investments is step one. Here's how Ziggma lets you act on it — something almost no consumer investing platform offers in a self-directed way.

1. Diagnose with the Impact dashboard

Connect your brokerage and Ziggma calculates Global Warming Potential, Portfolio Impact Distribution (Profound / Positive / Mixed / Negative), Climate Action, Sustainable Resource Use, and a Controversy Score across your holdings. You'll see which specific positions are heating your portfolio — Pitney Bowes at 2.1 °C, NVIDIA at 1.5 °C, Gilead at 1.5 °C — and which are dragging the average up.

2. Filter for cooler alternatives with the Stock Screener

This is where most users find their biggest wins. Open the Stock Screener, go to the Impact filter theme, and:

The Screener becomes a shortlist of replacement candidates that meet your climate threshold and your financial criteria at the same time.

3. Test trades before you make them

Once you've identified a candidate, use the Portfolio Optimizer to model the trade. It shows you how a buy or sell would shift your Diversification, Portfolio Quality, and Impact Score before you commit a dollar. You can iterate — sell a high-temperature holding, buy a screener pick, and watch the portfolio-level number come down.

A note on what the Optimizer does not do yet: it doesn't let you set Global Warming Potential as a direct optimization target. To reduce your portfolio's temperature, the path is Screener first, Optimizer second — use the Screener to find lower-impact holdings, then use the Optimizer to test how adding them reshapes your portfolio. Direct climate optimization is on our roadmap.

A worked example: from 2.4 °C to 1.9 °C

Take a portfolio heavily weighted toward US tech and industrials, sitting at 2.4 °C Global Warming Potential. The Impact dashboard flags three holdings as the biggest contributors: a logistics company at 2.6 °C, a midstream energy name at 3.1 °C, and a chemicals manufacturer at 2.8 °C.

In the Screener, applying a maximum GWP of 2.0 °C and a minimum 50% energy-from-renewables filter — still within the same sectors — surfaces eight candidate replacements, each with comparable market cap and a Ziggma Quality Score above the portfolio average.

Modeling two of those replacements in the Optimizer shows the portfolio shift from 2.4 °C to 1.9 °C, with no degradation in diversification and a modest improvement in dividend yield.

The point isn't that every portfolio works out this cleanly. The point is that the data and tools required to even attempt this trade — at the position level, on your real holdings — exist on Ziggma and almost nowhere else for self-directed investors.

Why this combination is rare

Most investors who care about climate are stuck choosing between a thematic ESG fund (where someone else picks the holdings and the methodology is opaque) and a regular brokerage (where climate data simply isn't surfaced). Ziggma sits in between: you keep direct ownership and control of your portfolio, and you get the institutional-grade impact data — temperature alignment, carbon intensity trends, renewable energy mix, controversies — that's normally locked inside professional terminals.

You decide what "climate-aligned" means for your portfolio. Ziggma gives you the numbers and the tools to get there.

Ready to lower your portfolio's temperature?

Connect your brokerage in two minutes to see your portfolio's Global Warming Potential, identify the holdings pulling it off course, and screen for climate-aligned alternatives. Free to try, no credit card required.

Beyond stock selection

Implied Temperature Rise is one lens. A complete climate-aligned investing approach also considers:

If you're ready to act on what you find, our best fossil-free stocks for 2026 gives you a quality-screened starting point for replacing high-exposure holdings.

FAQ

FAQ: Reducing the Climate Impact of Your Portfolio

Implied Temperature Rise is an estimate of how much global warming the world would experience by 2100 if the entire economy operated like the companies in your portfolio. It is expressed in degrees Celsius — for example, 1.5°C, 2.0°C, or 2.8°C — and is calculated from each company's emissions trajectory and decarbonization commitments, benchmarked against science-based pathways aligned with the Paris Agreement. A portfolio at 1.5°C is aligned with the most ambitious climate target; one at 3°C or above is on a high-warming trajectory. For a full breakdown of what these numbers mean in practice, see our guide on how to build a fossil-free portfolio.

The metric displayed in the Ziggma app as "Global Warming Potential" is technically Implied Temperature Rise. We use the more intuitive label because it communicates the concept faster to investors who are not climate scientists. In formal climate science, "Global Warming Potential" refers to a coefficient comparing the warming effect of different greenhouse gases — for instance, methane versus CO₂. The number you see in Ziggma is ITR: a portfolio-level temperature alignment figure, not the scientific GWP coefficient.

For each holding, Ziggma displays Climate Action score, Global Warming Potential (ITR in °C), Net-Zero Target Date, Carbon Intensity, Carbon Intensity Change over time, Percentage of Energy from Renewable and Non-renewable Sources, Sustainable Resource Use, Waste Recycling, Sustainable Water Use, and a Controversy Score covering ESG incidents in the past two years. All data is sourced from ACA Ethos — institutional-grade, methodology-transparent impact data. For more on what the data covers and how it is sourced, see the impact data overview.

There are three steps. First, connect your brokerage to see your portfolio's Global Warming Potential and identify which holdings are pulling the average up. Second, open the Stock Screener and apply Impact filters — set a maximum Global Warming Potential (for example, 2.0°C) and a minimum percentage of energy from renewables to surface lower-impact alternatives that also meet your financial criteria. Third, use the Portfolio Optimizer to test how buying or selling specific holdings would reshape your portfolio before you commit a trade.

Ziggma is a self-directed portfolio management platform, not a fund. You keep direct ownership of your investments in your own brokerage account. Ziggma adds an analytics layer on top — covering performance, diversification, quality, dividends, and climate impact — so you can make informed decisions about what to buy and sell yourself. This means you choose what "climate-aligned" means for your portfolio rather than delegating that judgment to a fund manager. See how Ziggma compares to other platforms in our Ziggma vs. Morningstar breakdown.

The Paris Agreement sets two targets: 1.5°C (most ambitious) and below 2.0°C (headline goal). For a self-directed investor, below 2.0°C is an achievable and meaningful target — most well-constructed fossil-free portfolios on Ziggma land between 1.4°C and 1.9°C. The S&P 500 currently reads approximately 4.1°C, so most diversified index fund investors are significantly above the Paris targets without realising it. Getting to below 2.0°C typically does not require a full portfolio overhaul — it usually means replacing the five to ten highest-temperature holdings with lower-impact alternatives in the same sector. See our curated list of best climate stocks for 2026 as a starting point for replacements.

Not necessarily — and the evidence increasingly suggests the opposite. Research from Schroders and Oxford Saïd Business School found that impact-driven equity portfolios outperformed the MSCI ACWI IMI in 8 out of 10 randomly constructed scenarios between 2010 and 2023, with lower volatility and smaller drawdowns. The structural reason is that companies with credible decarbonization plans tend to be operationally efficient, disciplined with capital, and positioned in markets with long-term policy tailwinds — characteristics that compound. The key is combining a climate filter with a quality filter rather than applying climate screens alone. For a full breakdown of the outperformance evidence, see our article on impact investing and market outperformance.

Ziggma's Impact dashboard shows your Global Warming Potential broken down by holding — so you can see exactly which positions are pulling your portfolio's temperature up and by how much. The display is position-level, not aggregate, which means you can identify the specific stocks or funds responsible rather than getting a blended number that obscures the source. Common surprises include logistics companies, chemicals manufacturers, midstream energy names, and broad index ETFs that hold fossil fuel producers at market weight. If you hold accounts at more than one broker, make sure all are connected — a holding at a second broker that you have not linked will not appear in the analysis. See how to track investments across multiple accounts for a complete consolidated view.

They are related but not identical. A fossil-free portfolio applies a hard exclusion — no companies that extract, produce, or primarily distribute coal, oil, or natural gas, regardless of their emissions trajectory. Reducing climate impact is a broader, forward-looking goal: it targets your portfolio's Implied Temperature Rise, which depends not just on whether a company is in fossil fuels but on its credible decarbonization path, carbon intensity trends, and renewable energy mix. A utility company that is actively transitioning away from coal may score better on ITR than a fossil-free industrial with no net-zero commitment. Most climate-aware investors use both: a fossil-free exclusion as a floor, and ITR targeting to optimize what remains. For a full comparison, see our guide to building a fossil-free portfolio.

Connect all your accounts to Ziggma — it supports connections to virtually any broker via secure, read-only authentication. Once all accounts are linked, the Impact dashboard calculates your Global Warming Potential, Portfolio Impact Distribution, and Climate Action score across your entire portfolio simultaneously, not account by account. This matters because you may appear climate-aligned within one account while holding high-temperature names at another broker that push your aggregate ITR significantly higher. Analyzing accounts in isolation is one of the most common reasons investors overestimate how climate-aligned their overall portfolio actually is. For a step-by-step guide to consolidating all your accounts, see how to analyze a stock portfolio across all your holdings.