Visualizing cause and effect of global warming

Unlike Indiana Jones (Harrison Ford) miscalculating the consequences of his actions, there is no miscalculating the cause and effect of greenhouse gas emissions. (Source: Lucasfilm Ltd.)Unlike Indiana Jones (Harrison Ford) miscalculating the consequences of his actions, there is no miscalculating the cause and effect of greenhouse gas emissions. (Source: Lucasfilm Ltd.)

In this era of big data, satellites, and other technological innovations that improve our understanding of the changing climate, it still can be difficult to grasp the scale of human-caused global warming.

  • If you live far from the sea, you may not worry that sea level rise still threatens your community.
  • If you are not involved in growing crops, you may not worry that a warming planet already is negatively impacting yields and nutritional value.
  • If you enjoy a robust seafood selection at your local market, you may not realize the variety belies the threat a warming ocean poses to global fish stocks.

A new study illustrates how the increase in warming global temperatures has a cascading effect throughout all aspects of life.

Cause, effect, climate-human interconnectivity

To demonstrate the cause and effect between today’s climate disruption and the ensuing risks to humanity, particularly in the context of food security, researchers have developed an approach to visualize the interconnectivity.

Flowchart of climate risk interconnections related to the food sector. (Source: Yokohata et al, 2019)

Flowchart of climate risk interconnections related to the food sector. (Source: Yokohata et al, 2019)

In the paper published in Earth’s Future, researchers illustrate the cause and effect of global warming as its impacts cascade through:

  • Natural and socioeconomic systems
  • Crop production
  • Food supply and security
  • Human health and well-being

In the Food sector example above, researchers illustrate how crop production is threatened by a variety of global-warming related risks, including rising temperatures, extreme heat events, and record floods. The flowchart visualization shows the interconnectivity as the risks impact the natural world, which affect crop production, and, ultimately, us.

The March 2019 flood damage in the Midwest is estimated to be more than $1.3 billion, but assigning a dollar value to damage fails to convey the interconnectivity between climate and humanity.

In a step-by-step cause-effect visualization below related to the decline in crop production, the researchers show the progression of impacts, starting with panel (a) and progressing through panel (d):

Network map of climate risk interconnection related to decline in crop production. Cause–effect relationships concerning (a) climate diver, (b) climate driver and natural system, (c) climate driver and natural and socioeconomic systems, and (d) climate driver and natural, socioeconomic, and human system are illustrated.

Network map of climate risk interconnection related to the term “decline in crop production.” Cause-effect relationships concerning (a) climate diver, (b) climate driver and natural system, (c) climate driver and natural and socioeconomic systems, and (d) climate driver and natural, socioeconomic, and human system are illustrated. (Source: Yokohata et al, 2019)

The visualization indicates how an increase in malnutrition, shown in panel (d), results from the destabilization of food supply (c), which results from a decline in crop production (b), which results from rising air temperatures, a decrease in precipitation, and an increase in extreme heat (a).

Whatever a man sows, this he will also reap

One thing I hadn’t considered is the concept of cause and effect in the Biblical context. Writing in a blog post about how cause and effect applies to relationships, Rev. Steve Hogg cites several examples from the Bible, including one from the Book of Galatians: “Whatever a man sows, this he will also reap.” Of course, greenhouse gas emissions and human-caused global warming weren’t wreaking havoc way back when, but the quote is wholly applicable to the climate crisis humanity faces today.

They’re all connected

In this prescient scene from "Total Recall," Everett (Marc Alaimo) explains to Richter (Michael Ironside) the relationship between global warming, crop production, and global food security: "They're all connected!"

In this prescient scene from “Total Recall,” Everett (Marc Alaimo, right) explains to Richter (Michael Ironside) the relationship between global warming, crop production, and global food security: “They’re all connected!” (Source: Carolco Pictures)

Overall, the researchers identified 253 causal relationships in the sectors prone to climate risks:

  1. Food
  2. Water
  3. Energy
  4. Industry and infrastructure
  5. Disaster and security
  6. Heatlh
  7. Ecosystems

The complexity of the cause-and-effect interconnectivity of global warming impacts makes it difficult to visualize, but interactive tools, such as the New York Times How Much Hotter Is Your Hometown Than When You Were Born tool, is a good example.

The visualization method developed by the researchers was based on a survey of climate-related literature as part of the Integrated Climate Assessment-Risk Uncertainty, and Society project.