Future of the Cryosphere

Climate Predictions

In Lab 4, you explored the history of the cryosphere and looked at indicators of past climate, including ice cores. Now, you will consider the future of the cryosphere in a changing climate and how scientists use models to make predictions.

Climate Models

Climate models are constructed using basic physical equations describing how the climate system works in three dimensions, as pictured in the graphic, right. State-of-the-art climate models now include equations that describe the processes of all of the Earth systems. These equations describe the ocean, the atmosphere, the land, hydrologic and cryospheric processes, terrestrial and oceanic carbon cycles, and atmospheric chemistry. Unlike weather forecasting, which describes the daily sequence of environmental conditions starting from a present state and working forward in time, climate models are based purely on the physics and chemistry of the Earth system.

To complete a climate model, the physical equations, which represent how the spheres interact, are coupled with scenarios (described below) of how Earth's human population, land use, and economy will evolve. Once a climate model is run, the model output data is compared with the observed data from the past. This process allows scientists to check the accuracy of the models.

Worldwide, various teams of scientists have modeled the next century of climate change and the subsequent impacts. While the models show that rising global temperatures generally characterize the future world, human behavior will determine how dramatic the changes may be.

What is a scenario?

A scenario is an image of a potential future that is based on historical knowledge and expectations of future change, as illustrated in the roots of the tree in the diagram on the right. The IPCC (Intergovernmental Panel on Climate Change) scenarios are based on a data-driven storyline (or narrative) of what events have occurred in the past and how the future may unfold.

There are four commonly used scenario families. They are labeled A1, A2, B1, and B2. The scenarios describe the relationships between the forces driving greenhouse gas and aerosol emissions and their potential future change during the 21st century for the globe.

Each storyline, and related scenario, represents a different projection of a set of influential factors including: demographic and social change, economic growth, technological innovation, and environmental developments, such as land-use change. These emission scenarios are used as input into climate models.

(Text adapted from: IPCC Special Report on Emissions Scenarios, 2007)

According to the Intergovernmental Panel on Climate Change (IPCC) , the four storylines combine two sets of divergent tendencies: one set varying between strong economic values and strong environmental values, the other set between increasing globalization and increasing regionalization. The storylines are summarized as follows (Nakicenovic et al., 2000):

  • A1 storyline and scenario family: a future world of very rapid economic growth, global population that peaks in mid-century and declines thereafter, and rapid introduction of new and more efficient technologies. A convergent world where there is much social interaction. The A1Fi, storyline is the most fossil fuel intensive (Fi).
  • A2 storyline and scenario family: a world of independently operating nations, with continuously increasing global population. Regionally oriented economic growth that is more fragmented and slower than in the other storylines.
  • B1 storyline and scenario family: a convergent world with the same global population as in the A1 storyline but with rapid changes in economic structures toward a service and information economy, with reductions in material consumption, and the introduction of clean and resource-efficient technologies.
  • B2 storyline and scenario family: a world in which the emphasis is on local solutions to economic, social, and environmental sustainability, with continuously increasing population (lower than A2) and intermediate economic development. This is the most conservative of the scenarios.

Try the climate change questionnaire and learn more about scenarios

So, what does this all mean to me, the individual?

Try the interactive questionnaire, below, to see how your own individual lifestyle choices play out in a scenario and subsequent climate. Repeat the questionnaire several times and compare your results.

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Questionnaire courtesy of The King's Centre for Visualization in Science

This interactive is not included in the EarthLabs iPad app. To view it, please use a Flash-enabled device.


How do individual lifestyle choices influence global climate change? Can one person really make a difference? Brainstorm and share ideas for changes in your lifestyle that you and your classmates and families can make.

Get a sense how much the temperature may increase

  1. First, go to the Climate Wizard Site ( This site may be offline. ) and select the Map of change (in temperature) showing the United States.
  2. Next, on the left under Future Climate Model, select the High A2 "Emission Scenario" and the "Ensemble Highest" General Circulation Model. Set the Time Period to Mid Century (2050s), and choose Map of Change. Select the Average Temperature measurement.

  3. Once you have observed the changes in the time period 2050, change the time period to the 2080s.

  4. Check the Factoid box in the upper right corner of the map to reveal climate-related facts from different locations across the nation.
  5. Checking In

    1. What is the projected mean temperature departure for Houston, TX in the 2050s?
    2. Which of the following cities is projected to see the greatest amount of warming by the 2080s?

Consider projected changes where you live

Zoom into your home state, region, or city on the ClimateWizard map to see the predicted future changes in temperature.


Put climate change in perspective by considering the following:
  • How old will you be in 2050, 2080?
  • How much will the temperature in most of the United States have changed by 2080?
  • Give several examples of how the increase in average temperature could impact your daily life.