The global climate deal reached in Paris last year is on the verge of entering into force.

By early October, the number of signatories to the pact exceeded the threshold necessary to take effect, with 74 nations accounting for nearly 60% of total global greenhouse gas emissions formally joining the Paris agreement.

Early in September, President Barack Obama and President Xi Jinping joined the Unites States and China to the Paris agreement, signing up the world’s two biggest carbon emitters. In early October, India became the 62nd nation to ratify the agreement. In early October, EU member nations and others joined, sealing the deal in advance of the next climate conference (COP22) scheduled to begin on November 7 in Marrakech, Morocco. There are now 197 nations as parties to the convention.

The Paris agreement requires each nation to set national targets for reducing or reining in its greenhouse gas emissions. Those targets are not legally binding, but countries must report on their progress and update their targets every five years.

The goal is to keep the global temperature increase “well below” 2 degrees Celsius and to pursue efforts to limit it to 1.5 degrees Celsius. Another goal is to cause greenhouse gas emissions to peak as soon as possible and achieve a balance between sources and sinks of greenhouse gases in the second half of the century. By 2020, $100 billion a year is to be dedicated to climate finance for developing countries with commitments of additional financing in the future. Once the deal comes into force, countries that have ratified it have to wait for a minimum of three years before they exit.

The United States and China together produce just shy of 39% of the world’s man-made carbon dioxide emissions, with India responsible for about 5%.

The US has pledged to cut its emissions by at least 26% over the next 15 years, compared to 2005 levels.  US Senate ratification is not required because the agreement is not considered a formal treaty. However, the Clean Power Plan the Obama administration is trying to implement, in the face of US court challenges, is a fundamental means by which the United States could reach its obligations under the Paris climate deal.

China announced a 2030 deadline for China’s emissions to stop rising and agreed in principle to a faster phasedown of super-polluting hydrofluorocarbons. India has committed to ensuring that at least 40% of its electricity will be generated from non-fossil sources by 2030.

Clean Power Plan

The main force of the Obama administration’s climate change policy went before a full panel of a US appeals court in Washington last month. The Clean Power Plan imposes the first national limits on carbon pollution from power plants, the largest source of greenhouse gas emissions in the nation.

The US Environmental Protection Agency finalized the Clean Power Plan and published emission guidelines for states to follow in developing plans limiting carbon emissions from existing plants in August 2015. The EPA left to the states to decide how best to meet the emissions goals in the first instance, but EPA will impose a plan on states that fail to submit their own plans or that submit inadequate plans.

The US Supreme Court blocked implementation pending a decision by the appeals court or further action in the Supreme Court in a 5-4 decision last February.

The case, now known as West Virginia v. U.S. Environmental Protection Agency, consolidates 157 petitioners in 39 lawsuits, including 27 states, numerous companies, trade associations and environmental groups. The 10-judge panel heard more than seven hours of argument in late September.

The Clean Power Plan was issued under section 111(d) of the Clean Air Act, a little-used provision that has never been employed as broadly before. The debate is whether requiring utilities to meet certain emissions standards under the Clean Power Plan falls within the agency’s Clean Air Act authority to determine the best system of emission reduction when setting emissions limits under section 111(d) of the Clean Air Act, or whether the agency has the authority to regulate power plant emissions at all.

The coalition of states challenging the plan argues that the case is about an illegal expansion of EPA power and will require standards that will cause some coal plants to close because of their comparatively carbon high emissions. The EPA estimates the annual costs of the plan are $7.3 billion to $8.8 billion in 2030, but some industry estimates put the annual cost much higher.

Supporters of the plan argue there is a delegation of authority to EPA to address new problems as they arise under the Clean Air Act, and that this includes climate change.

Indiana Bats

A federal appeals court agreed in August with opponents of an Ohio wind farm that the US Fish and Wildlife Service issued a permit to developer without fully considering ways to reduce deaths of endangered Indiana bats.

Buckeye Wind estimated that its 100-turbine wind farm would injure or kill 5.2 bats per year with certain controls in place, with no more than 26 Indiana bats killed in a five-year period. The company applied for an “incidental-take” permit. The US Fish and Wildlife Service said, when it approved the permit in 2013, that the proposal to lower turbine speeds during certain months met statutory standards, with the estimated take of 5.2 bats per year affecting neither the Midwest recovery unit of bats nor a local unit of a single maternity colony.

In March 2015, a lower court found no violation of the Administrative Procedures Act, the National Environmental Policy Act or the Endangered Species Act. It credited the finding by the USFWS that the minimization and mitigation measures “fully offset” the impact of the taking of Indiana bats, making it unnecessary for the agency to determine whether the plan was the maximum protection that can be “practically implemented.”

In a somewhat mixed August opinion, the appeals court partially reversed the lower court. It found that issuance of the permit was “arbitrary and capricious” and in violation of National Environmental Policy Act procedures because the federal agency did not analyze a sufficient number of alternatives to reduce the number of Indiana bats taken.

The court said that, while the National Environmental Policy Act does not require the agency to consider an “infinite array” of alternatives, it does require the agency to analyze a mid-range alternative that would take fewer bats while still enabling the wind farm to go forward.

It said the agency knew Buckeye Wind claimed that the maximum alternative it considered — which would have turned off the turbines at night from April to October — was not economically viable.

The court ruled that the agency should have considered whether an increased cut-in speed would still allow the project to go forward while protecting more Indiana bats.

The endangered Indiana bat has been central to a long-running battle against the proposed 100-turbine wind farm in Champaign County, Ohio. Although the species does not hibernate in the area, it migrates through the area during the spring and fall.

The case is Union Neighbors United, Inc. v. Sally Jewell.

Greater Sage Grouse

The Bureau of Land Management issued seven memoranda to its field offices in early September with guidance on how to implement new protections for the greater sage grouse.

The seven instructional memoranda follow amendments made to land management plans in 2015 that allowed federal regulators to avoid listing the greater sage grouse as a threatened species under the Endangered Species Act. The land use plans apply to federal lands managed by BLM and the US Forest Service.

The guidance is in response to state and stakeholder desires to see clear and consistent application of the agency’s management activities across the western greater sage grouse states while providing flexibility to respond to local situations and concerns.

The land use plans have been challenged in court in variety of lawsuits. Industry critics argue that the new guidance includes arbitrary prioritization of leases and permits and say the memoranda, mostly about methodology, fail to ease their concerns that the BLM might insist on impractical restrictions.

Hydro

Large hydroelectric power suppliers are lobbying the New York Public Service Commission to be included in the state’s new clean energy plan.

Hydro-Quebec and Brookfield Renewable Partners argue their hydroelectric plants should get the same subsidies for carbon-free electricity as those being given to wind, solar and nuclear power generators.

In August, the commission voted on a plan to get half of the state’s power from renewable-sourced electricity by 2030 in order to cut greenhouse gas emissions by 40% from 1990 levels. As part of the program, the state will provide credits to subsidize nuclear facilities as well as solar, wind, biomass and small hydro plants. Parties had until August 31 to file challenges to the plan, which is backed by New York Governor Andrew Cuomo.

Run-of-the-river hydroelectric facilities that have a capacity of five megawatts or less would qualify under the clean energy standard adopted by the commission, but petitions for rehearing on the issue of including larger plants are pending.

States have struggled with how and whether to account for large hydropower operations as part of their renewable energy goals. For example, California is under a mandate to get 50% of its electricity from solar power and wind farms, but it does not include large hydro plants as part of its target.