What Does NCA5 Mean for You?
If you’ve been online at all in the last few days, you might have heard about NCA5, or the Fifth National Climate Assessment. But if you aren’t familiar with the NCAs, or with climate science, what does NCA5 mean for you?
The National Climate Assessments are released approximately every four years by the US Global Change Research Program. They are the most authoritative climate science reports, including information about risks, impacts, and responses to climate change in the US. In other words, it’s a really big deal in the science and policy world.
There are lots of exciting, new materials in the NCA5, but one of the most exciting is the inclusion of art. In my opinion, this inclusion really brings together the environmental and social science of climate change. You can find all artwork submitted to the NCA5 here.
Here are all the chapters in the NCA5 - so much research and synthesis work went into this report! If you have the time and interest, it’s definitely worth reading the full report.
NCA5 Chapter List. Image Source.
The thought of reading the entire report might be overwhelming, or you might just not have the time - so, I’m going to give a really brief summary of the report here, summarize a couple chapters (Northern Great Plains and Southwest) a little more in depth, and provide some more resources at the end of this post.
Image Source: Lawrence Paul Yuxweluptun, from Sarah Macaulay & Co. Fine Art.
Super Brief Summary of NCA5: Overview
The overview introduces a few terms that are helpful to define before reading the rest of the report:
Mitigation: “measures to reduce the amount and rate of future climate change”
Adaptation: “the process of adjusting to an actual or expected environmental change and its effects”
Resilience: “the ability to prepare for threats and hazards, adapt to changing conditions, and withstand and recover rapidly from adverse conditions and disruptions”
Net-Zero: when emissions of greenhouse gases equal the amount we are storing or removing
Net Negative: when emissions of greenhouse gases are less than the amount we are storing or removing - in other words, we are taking in more greenhouse gases than we are putting out
Cascading Events: when one extreme event (natural disaster, pandemic, etc) causes an environmental, social, or economic chain reaction (for example, “climate-related shocks to the food supply chain have led to local to global impacts on food security and human migration patterns that affect US economic and national security interests.”)
Compound events: “the risk of two or more extreme events occurring simultaneously or in quick succession in the same region”
The NCA5 points out that greenhouse gas emissions in the US have actually decreased since their peak in 2007, largely due to new measures for energy efficiency and introduction of alternative energy sources. However, this decline is not enough to prevent us from experiencing worldwide effects of climate change; our current trajectory means we will exceed the goal of becoming net-zero by 2050.
This graph from the NCA5 shows “different scenarios of future carbon dioxide emissions are used to explore the range of possible climate futures”:
“FIGURE 1.4. The five scenarios shown (colored lines) demonstrate potential global carbon dioxide (CO2) emissions pathways modeled from 2015 through 2100, with the solid light gray line showing observed global CO2 emissions from 2000 to 2015. See Table 3 in the Guide to the Report for scenario definitions. Many projected impacts described in this report are based on a potential climate future defined by one or more of these scenarios for future CO2 emissions from human activities, the largest long-term driver of climate change. The vertical dashed line, labeled “Today,” marks the year 2023; the solid horizontal black line marks net-zero CO2 emissions. Adapted with permission from Figure TS.4 in Arias et al. 2021.” (Figure from NCA5)
We are already feeling the impacts of climate change. The US alone has seen a significant increase in deaths and damages due to climate-related disasters, and risks are increasing from cascading and compound events. Furthermore, “climate change exacerbates inequities.” Low-income communities, especially communities of color, are less equipped to deal with the impacts of climate change due to a historical and continuing institutional lack of support and resources.
NCA5 and the Rocky Mountain Region
I personally think of the Rocky Mountain region as New Mexico, Colorado, Wyoming, and Montana, and I generally post about this region the most. That being said, it can be really hard to define climate issues by state, simply because climate issues cross state boundaries. For example, increasing frequency and severity of droughts doesn’t just happen in Colorado, it happens all over the western United States. For this section, I’ll be summarizing some main points from the Northern Great Plains and Southwest chapters.
The NCA5 defines these regions by the following states:
Northern Great Plains: Montana, Wyoming, North Dakota, South Dakota, Nebraska
Southwest: Colorado, New Mexico, Arizona, Utah, Nevada, California
NCA5, Regions. Image Source.
Northern Great Plains
Photo Credit: Jarred Decker, Unsplash
The Northern Great Plains has already begun to experience extreme events; however, this will only increase, and we should expect “severe droughts… increases in hail frequency and size, floods, wildfire… rising temperatures… [and] greater variability in precipitation” (NCA5). This is harming the “physical, mental, and spiritual health” of residents of this region, particularly those in the agricultural sector whose livelihoods are impacted, as well as historically marginalized peoples, particularly Indigenous communities (NCA5).
While communities are adapting to climate-related impacts by shifting towards “innovative soil practices, new drought-management tools, and water-use partnerships” - and Tribal Nations are “leading efforts to incorporate Traditional Knowledge and governance into their adaptation plans” - “tensions and trade-offs” are rising (NCA5). Therefore, “energy demand, production, and policy” will need to adapt as climate change impacts increase across the region (NCA5).
TL;DR: “Rising temperatures and decreasing snowpack reduce water supply; increases in extreme heat, wildfire, and flooding harm physical and mental health; and livelihoods are at greater risk, especially in agriculture, recreation, and energy sectors.”
Southwest
Photo Credit: Connor Humiston, Unsplash
Water resources are a huge concern for the Southwest, and drought and increasing aridity (dryness) are endangering water resources (NCA5). We have been experiencing intensely increasing temperatures, which have in turn “intensified drought” and will “exacerbate existing water supply-demand imbalances” (NCA5). Precipitation patterns have been changing as well; the Southwest is “experiencing more intense precipitation events… which contribute to increased flooding” (NCA5). In may places in the Southwest, water management and utilities systems are not designed for this changing climate. Water management will have to adapt in order to “mitigate the impacts of these changes on people, the environment, and the economy” (NCA5).
Furthermore, drought will also affect agriculture in the Southwest, making it “more difficult to raise food and fiber…without major shifts to new strategies and technologies” (NCA5). The impacts on local economies and food security will be significant, but may be addressed by “incorporating Indigenous Knowledge with technical innovation” (NCA5).
While wildfires have always been a part of the ecosystems of the Southwest, we have recently “experienced unprecedented wildfire events… [where] fires in the region have become larger and more severe” (NCA5). The way that we have historically addressed wildfires, through large-scale fire suppression, has now caused a buildup of fuels that makes prescribed burns and other cultural burning (“traditional land stewardship practices and the application of Indigenous cultural fire”) very difficult (NCA5).
In the coastal Southwest, “large-scale marine heatwaves and harmful algal blooms” are causing significant and damaging impacts on marine ecosystems and economies (NCA5). Sea level rise is also a concern, along with flooding and saltwater intrusion, which “will have severe and disproportionate effects on infrastructure, communities, and natural resources” (NCA5).
All of these impacts are affecting human health in the Southwest; “individuals particularly vulnerable to increasing climate change impacts include older adults, outdoor workers, and people with local income,” as well as communities of color (NCA5). Adaptation and mitigation measures will need to be taken to prevent against, or at least decrease the impacts caused by, anthropogenic climate change.
TL;DR: “Intensifying drought and decreases in groundwater recharge reduce water supply; economic losses to farmers and ranchers increase; and extreme heat, drought, wildfire smoke, and coastal flooding harm physical and mental health.”
Key Takeaways
Inclusion of social science and equity. I haven’t read previous NCAs in detail, but something that stood out to me about this one was the integration of social science and equity in pretty much every aspect of the document. The authors took care to mention that the effects of climate change are not equally felt among different populations, and that this can and should affect how we discuss mitigation and adaptation. Furthermore, the diversity of authors and their experiences is notable, as is the inclusion of both an Indigenous Peoples chapter and a Social Systems and Justice chapter!
The NCA5 is significant for both science and policy. It’s really important to have these data and supporting information in official government documentation; this will be a huge help to policymakers and managers going forward, since they can reference an official, up-to-date government document that supports that climate change is affecting their region.
Political leadership acknowledges anthropomorphic climate change. After the previous administration’s dismissal of anthropomorphic (human-caused) climate change, and now in a time where people are so misinformed about science, it is crucial for political leadership to acknowledge that science is real. It’s really significant that this administration is willing to support the publication of documents discussing climate change, its impacts, and not only what we need to do to be more prepared, but that it isn’t too late to stop or even reverse some of the destruction we are experiencing.
Remember, this was a tiny snapshot of the information included in NCA5, and I may not have discussed specifics related to your region in this post. Make sure to check out the resources below for more information!
More Resources
If you’re interested, definitely read the full NCA5!
There is also a companion podcast for the NCA5.
This White House Fact Sheet gives a great overview of the issues facing each region of the US.
Read about the contributions of the NC CASC (North Central Adaptation Science Center) here!
Check out the NCA5 Interactive Atlas, and/or check out my quick guide to using this tool here!
You can find all artwork submitted to the NCA5 here!
