Climate change will be on the agenda as Prime Minister Shinzo Abe meets with President Obama this week, heightening anticipation about what Japan—the world’s fifth-largest greenhouse gas emitter—will release in its forthcoming post-2020 climate action plan. While recently leaked reports suggest that the Japanese government is considering a target of reducing its emissions 20 or 26 percent below 2013 levels by 2030, new research shows that the country can go much further.Research from the Institute for Global Environmental Strategies (IGES), in partnership with WRI’s Open Climate Network, suggests that Japan can reduce its emissions 25 percent below 1990 levels (or 31 percent below 2013 levels) by 2030 through additional investments in renewable energy and energy efficiency, even without using nuclear power. A 30 percent reduction from 1990 levels (or 37 percent below 2013 levels) by 2030 is possible if the government proceeds with plans to bring some nuclear reactors back online and makes significant investments in renewable energy and energy efficiency.Unofficial Proposals for Japan’s Post-2020 Target Are InsufficientCritics decried the 20 percent target as inadequate, citing Japan’s choice of base year (2013, which was the second-highest year of annual emissions on record for the country) and its relative lack of ambition compared to other proposals put forth by developed countries. The United States has already set a goal of a 26-28 percent reduction in total emissions from 2005 levels by 2025, and other major emitters, including the EU-28 and Mexico, also put forth more ambitious targets. Even if Japan increased its target to a 26 percent reduction below 2013 levels by 2030, which some outlets say the government is considering, it would still be less aggressive than the EU and U.S. targets when compared on the basis of 1990 or 2005 base years.Importantly, Japan’s target is being decided amidst a recent rise in the country’s emissions. This trend is largely a result of the government’s decision to shut down its entire fleet of nuclear reactors following the Fukushima disaster in 2011 and replace its nuclear generation with a more carbon-intensive fuel mix. Since then, Japan has been contemplating its long-term energy policy, and in particular, the role of energy efficiency and energy sources such as coal, natural gas, nuclear and renewables in meeting future energy demand.Ambitious GHG Reductions Are Within Reach for JapanIGES authors examined nearly 50 scenarios of future greenhouse gas emissions pathways for Japan. These scenarios serve as illustrative examples to shed light on the range of options – and associated levels of effort – available. To achieve greenhouse gas reductions consistent with a moderate probability of limiting global temperature rise to 2 degrees C (which scientists say is necessary to avoid the worst effects of climate change), the study found:A 25 percent reduction of GHG emissions from 1990 levels by 2030 is achievable with no nuclear power, assuming a scale-up of renewable generation to 35 percent (from a share of approximately 13 percent of total electricity generation as of 2013), a 25 percent reduction of final energy use, and a 60 percent gas-fired power share in total fossil fuel power generation (gas-power ratio).With an estimated 15 percent share of nuclear power (approximately equivalent to restarting existing capacity), the country could reduce its emissions 25 percent below 1990 levels by 2030 assuming a 30 percent renewables share, a 20 percent reduction of final energy use and a 60 percent gas-power ratio.With a 15 percent nuclear power share, the country could also achieve a 30 percent emissions reduction by 2030 by reducing final energy use to 25 percent of current use rates.Japan At a CrossroadJapan previously pledged a long-term goal of reducing its emissions by 80 percent from 1990 levels by 2050, a level consistent with limiting global warming to 2 degrees C (3.6 degrees F). This target is ambitious, but it’s achievable so long as the country sets itself on this trajectory with its post-2020 contribution.Early signals from this week’s Japan-U.S. dialogues indicate Japan’s intent to submit an ambitious target. With the world watching, Japan’s government will soon choose whether or not it reaffirms its leadership on combating climate change and doubles-down on a clean energy future.