Human-caused climate change is here. According to the latest report by the highest authority on climate disruption, the Intergovernmental Panel on Climate Change: “It is very likely that heat waves will occur more often and last longer, and that extreme precipitation events will become more intense and frequent in many regions.” Translation: more historic floods, concrete-melting heat and wildfires. In the Arctic, warmer temperatures, melting ice sheets, thawing permafrost and eroding coastlines are changing the landscape at a dramatic rate.

Christiana Figueres, head of the UN Framework Convention on Climate Change (UNFCCC), has been tirelessly pressing for “transformational climate action.” Given that the first nine months of 2015 have exceeded previous global temperature records, action is the operative word.

From November 30 to December 11, an estimated 40,000 people, including government leaders from 194 countries and representatives from the European Union, UN agencies and international NGOs, will gather in Paris to hammer out a new international agreement on climate change.

COP21 stands for the 21st session of the Conference of the Parties to the UNFCCC. The parties, or heads of state, have met every year for the last two decades to figure out how to curb greenhouse gas emissions. Greenhouse gases (GHG) include carbon dioxide, methane, nitrous oxide and the like, that cause global warming. At the current rate of global GHG emissions, the world is headed for an increase of about 4C by 2100. But scientists say governments need to keep emissions to levels that will hold warming to 2C by the end of the century to avoid catastrophic changes to food production, sea levels, fishing and wildlife. The goal of COP21 is to create a strong, binding framework to stabilize GHG emissions within the acceptable range.

Here are five things you should know about the summit:

1. This time, it’s different

COP21 participants have learned from past negotiation failures. This conference has been four years in the making, and nations have already submitted intended nationally defined contributions, or INDCs, that outline the steps they will take to address climate change within their own countries. Two major emitters, the United States and China, are now engaged, and the E.U. has set bold mitigation targets. Other nations are now under pressure to ramp up their own efforts.

Because the UNFCCC upholds the principle of “common but differentiated responsibilities,” the nature of these contributions vary. Contributions can come in the form of mitigation efforts (i.e. reducing GHG emissions by cutting back on fossil-fuel use) and adaptation plans (i.e. providing farmers with access to drought-tolerant crops).

Thus far, these contribution targets will not keep warming within the 2C range, but the expectation is that nations will raise their targets to reach it.

2. There’s support for alternatives

The market will not spawn green energy alternatives quickly enough without help. Industrialized nations must regulate emissions, invest in alternatives and establish market-based instruments such as carbon trading schemes.

Low-carbon futures are real and tangible. According to market forecasts from the International Energy Agency, China will claim a whopping 40 percent of all renewable energy gains from 2015-2020. Wind is now the cheapest source of energy in the UK and Germany.

COP21 highlights these efforts and encourages knowledge-sharing to inspire solutions. A new Carbon Pricing Panel combines forces from the World Bank, the International Monetary Fund, members of the OECD and major global corporations to spearhead a framework of carbon pricing that encourages critical investment in renewables.

3. The Arctic is watching

The Arctic is ground-zero for climate disruption. Four million people are spread across the eight states with territory north of the Arctic Circle, and they have been disproportionately affected by the world’s carbon-based development. The Arctic is warming at more than twice the rate of southern latitudes. Indigenous populations living in the Arctic are particularly vulnerable to the impacts of climate change because sea ice, permafrost and wildlife provide them with safe transportation, food and traditional cultural activities.

Because the U.N. is an organization of states, the Arctic has been largely neglected from previous UNFCCC negotiations. This may change at COP21. In April, the U.S. took over as chair of the Arctic Council, an intergovernmental forum that addresses Arctic issues, and it has expressed a newfound interest in addressing climate change in the circumpolar world.

As a permanent participant of the Arctic Council, the Inuit Circumpolar Council is sending a delegation to COP21 and will host several side events to highlight regional concerns. It is advocating for adaptation assistance, perhaps through a special fund, to address Arctic-specific climate disruption. Arctic experts, such as Sheila Watt-Cloutier, remain optimistic that the Paris talks will yield measurable outcomes.

4. It’s about money – and ethics

Big investments will be needed to address anthropogenic climate change. This brings up the ethical question of who should pay. People in the Global South and the Arctic feel the impacts of climate change the most, yet they are the least responsible for it.

Wealthy nations and private organizations have agreed to mobilize $100 billion a year through the Green Climate Fund starting in 2020 to help emerging economies and vulnerable societies mitigate climate change impacts and reach emissions targets. This is a huge step forward. It shifts the discussion from a “them and us” divide to a global consensus requiring a fair distribution of responsibilities and commitments.

5. We’ve come a long way

Nearly 200 countries have agreed on the fundamentals:

• Climate change must be addressed to keep within a two-degree temperature rise;

• Global economic powerhouses have come up with innovative ways to price carbon and foster investment in alternatives; and

• UNFCCC nations have agreed that those who are most responsible for carbon emissions in the atmosphere should be assisting those suffering the consequences.

No one doubts the wide capabilities and ingenuity of our species. The only thing missing is unanimous political will. Though a serious obstacle, it’s a simple choice: we will or we won’t.

Top image: France’s President Francois Hollande is hosting major U.N. talks on climate change in Paris this week. (Thibault Camus, Pool/AP Photo)