What is the fate of CO2 produced by fossil fuel combustion? part of Quantitative Skills:Activity Collection
Paul Quay
A box model is used to simulate the build up of carbon dioxide in the atmosphere during the industrial era and predict the future increase in atmospheric CO2 levels during the next century.

Estimating Exchange Rates of Water in Embayments using Simple Budget Equations. part of Quantitative Skills:Activity Collection
Keith Sverdrup, National Science Foundation
Simple budgets may be used to estimate the exchange of water in embayments that capitalize on the concept of steady state and conservation principals. This is especially true for bays that experience a significant exchange of freshwater. This exchange of freshwater may reduce the average salt concentration in the bay compared to seawater if it involves addition of freshwater from rivers, R, and/or precipitation, P. Alternatively, it may increase the average salt concentration in the bay compared to seawater if there is relatively little river input and high evaporation, E. Since freshwater input changes the salt concentration in the bay, and salt is a conservative material, it is possible to combine two steady state budgets for a bay, one for salt and one for water, to solve for the magnitude of the water flows that enter and exit the bay mouth. Students will make actual calculations for the inflow and outflow of water to Puget Sound, Washington and the Mediterranean Sea and compare them to actual measured values.

Investigating dimensions of the solar system part of Quantitative Skills:Activity Collection
This page authored by Leslie Kanat, Johnson State College; Francisco San Juan, Elizabeth City State University; Steven Schafersman, CyberComputing Scientific Services; Michael Stewart, University of Illinois—Urbana Champaign
Planetary data are used to investigate and evaluate the Nebular Hypothesis.

Calculation of the Magnitude of Lunar and Solar Tidal Forces on the Earth part of Quantitative Skills:Activity Collection
Randal Mandock, Clark Atlanta University; Randal Mandock, Clark Atlanta University
Project in which students calculate the magnitude of lunar and solar tidal forces on the earth. They calculate the solar tidal effect relative to the lunar tidal effect and the relative solar tidal effect for spring-tide conditions.

ELIMINATING TRAYS IN THE CAFETERIA: BENEFITS TO THE PLANET AND TO ECONOMIC COSTS part of SISL:2012 Sustainability in Math Workshop:Activities
Dianne Marquart
In this activity, students will investigate the economic and environmental benefits of eliminating food trays in the cafeteria at their college.

Continental Crust Mass Balance Calculation part of Quantitative Skills:Activity Collection
Jennifer Wenner, University of Wisconsin-Oshkosh
A quantitative skills-intensive exercise using data from the Mineral Mountains, Utah, to calculate mass balance and to address the "space problem" involved with emplacing plutons into the crust.

Density of the Earth - How to Solve It part of Quantitative Skills:Activity Collection
Len Vacher, University of South Florida
This module addresses the real problem of determining the density of the Earth and invites the student to figure out how to solve the problem.

How many sand grains on a beach? part of Quantitative Skills:Activity Collection
Alan Whittington, The University of Texas at San Antonio
Short exercise designed to give students practice in determining what information is needed to answer a question, estimating an answer, and calculating an answer (including unit conversions and scientific notation). Emphasizes the relevance of large numbers to society (population, debt, etc).

Modeling: (1) Revenue Neutral Carbon Taxes; (2) Accelerated atmospheric C02 concentrations part of SISL:2012 Sustainability in Math Workshop:Activities
Martin Walter, University of Colorado at Boulder
Design a revenue neutral carbon tax and a plan for implementation; together with a model for what happens if we do not institute such a tax-system.

Kepler's Third Law - The Equation part of Quantitative Skills:Activity Collection
Len Vacher, University of South Florida
In this module, students are asked to devise a simple relationship between the sidereal period and orbital radius.