Chapter 1: The Current Climate Reality

The latest report from the Intergovernmental Panel on Climate Change (IPCC) paints a grim picture, indicating that the repercussions of human-induced emissions will persist for centuries, if not longer. Despite this unsettling news, it underscores a crucial point: not all climate disasters are unavoidable. The report emphasizes that every half-degree of temperature increase that can be prevented significantly alters the future of our planet, especially concerning extreme weather events like heatwaves, rainfall, and drought.

In November 2020, Venice experienced severe flooding in its iconic Piazza San Marco. This event, among many others, highlights the urgent need for action against climate change.

The report, generated by a collaborative effort of hundreds of scientists, revealed that human activities have caused a temperature increase of 1.1 degrees Celsius over the past 170 years. Glacial melting and rising sea levels will continue for thousands of years, regardless of future emissions reductions.

However, Youba Sokona, the IPCC's vice-chair, pointed out a hopeful perspective, stating, “We are at a pivotal moment to change our trajectory.” This assertion provides a glimmer of optimism amidst the challenging realities presented.

Section 1.1: Emissions and Temperature Projections

In the worst-case scenario projected by the IPCC, global emissions could double by 2050, leading to an average temperature rise of 2.4 degrees Celsius between 2041 and 2060. Conversely, a more favorable scenario suggests that temperatures could rise by just 1.5 degrees by 2040, potentially stabilizing by the century's end. This indicates that there is still an opportunity for meaningful action.

“It is highly likely that we can limit the rise in global surface temperature through swift and significant reductions in greenhouse gas emissions,” the authors of the report asserted.

Subsection 1.1.1: The Path Forward

During the 2015 World Climate Change Conference (COP21) near Paris, leaders committed to cutting greenhouse gas emissions to prevent global temperatures from rising more than 1.5 degrees Celsius above pre-industrial levels. Yet, the IPCC warns that we are likely to exceed this threshold in the next two decades.

Nevertheless, scientists believe that avoiding a 2-degree increase is still achievable. Greg Flato, a climate scientist involved in the report, remarked, “While it’s likely we’ll surpass 1.5 degrees, there is a path to slightly exceed it and then stabilize through significant emissions reductions by mid-century.”

In 2020, global carbon emissions saw a notable decrease of 2.5 billion tons, primarily due to pandemic-related restrictions that reduced transportation and energy usage. This decline, approximately 6% from the previous year, demonstrates our capacity for rapid behavioral change.

The IPCC report highlights that each trillion tons of carbon emissions results in an approximate 0.45-degree temperature increase. To remain under the critical 2-degree threshold, humanity has about 900 billion tons of carbon remaining in its budget. Given that emissions reached about 37 billion tons in 2019, this rate suggests we have roughly 25 years before exceeding this limit.

Chapter 2: The Importance of Mitigation

Every fraction of a degree can significantly impact our climate. Preventing an increase of even half a degree could mean the difference between extreme and manageable weather events. At 2 degrees of warming, the likelihood of experiencing severe droughts and heatwaves would rise considerably.

The IPCC discovered that at 2 degrees, the chances of facing at least three months of drought annually increase from about 20% to 35%. Additionally, the Atlantic Meridional Overturning Circulation (AMOC), a crucial system of ocean currents, could lose nearly 30% of its pre-industrial strength within this temperature range. This change would drastically affect weather patterns, potentially leading to harsher winters in some regions and more frequent heatwaves in others.

As global temperatures rise, ice sheets, glaciers, and permafrost will diminish, releasing stored carbon and further exacerbating warming. The IPCC estimates that with every degree of warming, the top three meters of permafrost could lose 20-30% of its volume.

Even if not all crises are averted, the report provides essential insights for policymakers. “Understanding what lies ahead empowers us to take proactive measures for the coming decades,” stated Alex Ruane, a lead author of the report. “This serves as a roadmap for the changes we must prepare for,” he added, expressing a sense of optimism despite the challenges.

In Rebecca Solnit's talk, "Not Too Late: Changing the Climate Story from Despair to Possibility," she discusses the power of optimism and action in the face of climate change. This perspective is crucial for inspiring change.

Conversely, the video titled "OK, climate change is real. But it's too late to do anything" presents a sobering take on the urgency of the climate crisis. It’s essential to engage with diverse viewpoints to fully understand the complexities of this issue.