When people discuss “grand challenges” facing our world today, defined often as “technically complex societal problems that have stubbornly defied solution” (Branscomb). While organizations such as USAID have several “grand challenges” which define their organizational priorities, global climate change is seen as the quintessential “Grand Challenge”; other environmental issues such as urbanization and deforestation also often take the fore. But just as the solutions for grand challenges require a vast and complex network, the challenges themselves also possess a network of further causes and effects, which can magnify understood problems into issues equally deserving of the moniker “Grand Challenge”.

To give an example, urban flooding has been extensively studied and understood; cities would plan for a variable amount of rain which would need to be drained away in quick order. Yet, as we have seen most recently in the Houston, Texas urban area, climate change and increasing urbanization have both exacerbated the potential of flooding events. Increasing sea-level temperatures, particularly within the Gulf of Mexico, strengthen hurricanes, elevating the frequency of exceptional weather events to form a new statistical norm.

The alarming frequency of “hundred-year” storms is not the only factor in worsening floods. The devastation of coastal cities multiplies as cities in flood-prone areas develop over lakes, parks, and other natural formations which might absorb some floodwater. Without these natural drains, more neighborhoods become inundated by higher levels of flooding, worsening the issue even beyond what the increased intensity of storms would do alone.

The use of “grand challenge” in numerous fields is a fairly recent development, designed to evoke ideas of heroism and struggle in what might otherwise be mundane or overtly technical tasks. The factors surrounding grand challenges are not a simple knot which can be undone with a singular “silver bullet” solution, but a Gordian knot which can only be untangled with great effort and knowledge. Even as one challenge’s solution is sought, however, we cannot lose sight of other challenges woven into the same rope.