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What-If

Explore what could change.

Choose a place, a documented issue and one of its documented interventions, then set how far it goes.

ILLUSTRATIVE SCENARIO — NOT A SCIENTIFIC PREDICTION. Built from documented causes, impacts and solutions plus general qualitative patterns. It contains no modelled numbers.

3 · Intervention
PilotScaledTransformative

Adopted across much of the area, with dedicated budgets and enforcement.

Illustrative scenario

What if Karachi took a scaled approach to “Heat action plans”?

Starting point · documented

ClimateSeverity: High
Extreme heat in Karachi

Humid heat events in a coastal megacity create serious health risk, especially during power interruptions.

The intervention · documented

Heat action plans

Early warning, public advisories, cooling centres and pre-positioned medical response before forecast heat events.

Reduces heat-related illness and death; the approach is proven in several South Asian cities.

Schematic direction of change

Adaptation reduces exposure and harm, but the underlying hazard continues to be shaped by global greenhouse gas emissions.

Schematic, unitless illustration: relative pressure over time without the intervention compared with the intervention in place. Not based on measured data.NowLonger term →Relative pressure (unitless)
Without the intervention With the interventionSchematic shape only — no data, units or dates.

Causes this could address

  • Humid coastal climateHigh humidity limits evaporative cooling, so the body struggles to shed heat even at moderate air temperatures.
  • Urban heat islandDense construction, dark surfaces and limited vegetation keep built-up areas warmer than surroundings, especially at night.
  • Unreliable electricity supplyPower interruptions during peak demand remove access to fans and cooling exactly when risk is highest.

Impacts that could ease

  • Heat-related illness and deathThe 2015 heatwave produced mass casualties, with hospitals overwhelmed by heatstroke and dehydration cases.
  • Occupational risk for outdoor workersConstruction workers, street vendors and transport workers face sustained exposure with limited opportunity to rest or cool.

Wider reach at higher intensity is an assumption of this illustration.

How change might unfold

  1. Near term

    Early warning and preparedness measures can reduce harm quickly.

  2. Medium term

    Infrastructure and urban design changes reduce exposure as they are built out.

  3. Long term

    Protection must keep pace with a hazard that continues to intensify unless global emissions fall.

Faded stages are less likely to be reached at scaled intensity.

What this would not change

Local action cannot stop global warming; without global emission cuts the baseline pressure keeps rising.

What it depends on

  • Sustained funding and institutional capacity
  • Consistent enforcement and monitoring
  • Local stakeholder support
  • Participation of affected communities

ILLUSTRATIVE SCENARIO — NOT A SCIENTIFIC PREDICTION. Built from documented causes, impacts and solutions plus general qualitative patterns. It contains no modelled numbers.

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