Reducing carbon dioxide emissions isn’t enough. The stark report in early October by the Intergovernmental Panel on Climate Change, exhorting companies and countries to move quicker to throttle global warming, is fueling heightened interest in high-tech and low-tech solutions for sucking the infamous greenhouse gas out of the atmosphere."It’s necessary no matter what we do," said Kate Gordon, partner with the sustainability team at investment firm RIDGE-LANE, during a plenary session at VERGE 18, produced by GreenBiz Group. "It’s a range of everything from planting trees all the way to engineered solutions."This is far from new news, but it does signal a new sense of urgency when it comes to taking action. There’s a very practical motivation for speeding things up: carbon removal represents not just our best hope for limiting planetary temperature increases to less than 1.5 degrees Celsius, the field offers very real revenue opportunities for those willing to think about the problem differently.Exhibit A: Occidental Petroleum is seriously studying a plan to build carbon capture plants that it could leverage to improve oil recovery. The industry already pumps at least 68 million tons of CO2 into fields annually, a process that forces stranded oil to the surface while neutralizing the impact of those emissions. It’s a range of everything from planting trees all the way to engineered solutions. "The opportunity is to aggressively work with emitters to capture their CO2 and put it into the ground," said Charlene Russell, vice president of low-carbon solutions for Occidental, during the VERGE 18 session in Oakland, California, last week. The "45Q" tax credit, which provides incentives to companies seeking to invest in certain sequestration processes, has made this path more economically viable, she said. The credit (passed into law as part of the tax package earlier this year) pays $10 per metric ton for enhanced oil recovery applications — an amount that will increase to $35 per metric ton by 2024. Carbon capture approaches that store CO2 in "geologic formations" are eligible for $50 per ton. You won’t be surprised to hear that Occidental was a strong supporter of that legislation.For those skeptical of the industry’s motive, Gordon later offered this reality check: Fossil fuels companies have amassed decades of knowledge when it comes to exploration and geological expertise accompanied by massive research and development budgets. "I would hate to see that asset off the table," she said. "Oil companies should be diversifying into carbon management."Already "hundreds" of companies are focused on the problem of not just capturing and sequestering CO2 but turning it into a component of building materials or durable carbon components or transforming it into fuel, said Julio Friedmann, a former Department of Energy staffer and expert in "carbon wrangling" techniques currently affiliated with Columbia University. Two of his ready examples: CarbonCure and Solidia, both Canadian companies that use waste CO2 to produce concrete (traditionally one of the most carbon-intensive industrial processes on a global basis). Rather than focusing just on investment in buying carbon offsets (credits for projects such as afforestation meant to negate the impact of emissions), companies should think more about supporting what Friedmann has dubbed "inset" approaches — technologies and processes that turn CO2 as a component, such as the carbon-centric concrete example Oil companies should be diversifying into carbon management. "We want to create a world in which we emit less than we take up. … This is not science fiction," he said.Carbon removal could create new opportunities in rural regions, which could benefit from approaches focused on using CO2 to reinvigorate soil health, or in developing economies such as India and China that need to invest in infrastructure while mitigating emissions. Sequestering carbon in concrete and other building materials represents a real opportunity for innovation in both countries, Gordon suggested.  Real-world solutions are bubbling upThe World Resources Institute (WRI) has identified six options that it believes will be instrumental in scaling carbon removal:1. Forests: Every acre of land that is restored to temperate forest has the potential to sequester 3 metric tons of CO2 annually. The upside of this approach is that it is relatively less expensive than technological approaches.2. Farms: Planting cover crops during the time when fields are otherwise bare, for example, can improve the soil’s ability to capture and store CO2 by up to one-half metric ton per year.3. Bio-energy with built-in carbon capture and storage: The idea is to combine technologies for generating power from biomass (organic materials that are used to run processes in the industrial and transportation sector) with those that capture the embodied carbon and return it to the ground.4. Direct air capture: This refers to systems that essentially scrub CO2 out of the atmosphere, and that are often sited at the generation source for a power plant or industrial facility. One company attracting considerable attention for its solution is Climeworks, which just opened its third demonstration facility. Another one we’re watching is Noble Thermodynamic, a startup founded by Cyclotron Road that is working on equipment to remove the CO2 related with using natural gas or hydrogen engines. The downside of this option, at least right now, is that it can cost at least $94 to $232 per metric ton.5. Seawater capture: The U.S. Navy is developing prototypes for systems that would draw the CO2 out of seawater and convert it into a fuel source for ocean-going vessels.6. Enhanced weathering: The idea (a very nascent one) is to turn CO2 from a gas into a solid substance more quickly; this process happens over time, but certain minerals can help accelerate the process. "There is more work to be done to map out cost-effective and prudent applications of this approach," according to WRI experts.