Simple mass balance model for lakes, based on the Vollenweider equation:

dMw/dt = Min - sMw - Mout

This model provides a dynamic simulation of the Sverdrup (1953) paper on the vernal blooming of phytoplankton.

The model simulates the dynamics of the mixed layer over the year, and illustrates how it's depth variation leads to conditions that trigger the spring bloom. In order for the bloom to occur, production of algae in the water column must exceed respiration.

This can only occur if vertical mixing cannot transport algae into deeper, darker water, for long periods, where they are unable to grow.

Sverdrup, H.U., 1953. On conditions for the vernal blooming of phytoplankton. J. Cons. Perm. Int. Exp. Mer, 18: 287-295

In Chile, 60% of its population are exposed to levels of Particulate Matter (PM) above international standards. Air Pollution is causing 4,000 premature deaths per year, including health costs over US$8 billion.

Modeling forest succession in a northeast deciduous forest.

This model explains the primary production of phytoplankton, forced by light and nutrients over a year period.

Simple mass balance model for lakes, based on the Vollenweider equation:

dMw/dt = Min - sMw - Mout

The model was first used in the 1960s to determine the phosphorus concentration in lakes and reservoirs, for eutrophication assessment.

Simple (Kind of) food web of the Cane Toad Species. Includes different levels of consumers including predators.

In Chile, 60% of its population are exposed to levels of Particulate Matter (PM) above international standards. Air Pollution is causing 4,000 premature deaths per year, including health costs over US$8 billion.

B

With Our-Green-Spine we have discovered new insights how trees / forest / green structures are part of the managing system of controlling the temperature of our Earth via their cooling capacity by using water and influencing the water cycle. We want to translate our insights in a climate model. People who to join us please send an email to marcel.planb@gmail.com.
Thanks, Marcel de Berg

Two households with PV systems and electric vehicles sharing a battery and connected to the grid. What are the advantages?

This model prototypes the working of an Smart Grid with Electric Vehicles

The objective is testing the theoretical advantages of batteries (also batteries in Electric Vehicles) in combination with renewable energies. The model considers two houses, that store energy both in Electric Vehicles (Vehicle to Grid), and in a communal battery.

Except when specified otherwise, the units of all variables are expressed in W/h.

Press "Story" in the lower bar for a guided tour over the model. Better seen at 50% zoom.

by Carlos Varela (cvarela@gmx.at)

In Chile, 60% of its population are exposed to levels of Particulate Matter (PM) above international standards. Air Pollution is causing 4,000 premature deaths per year, including health costs over US$8 billion.

From Jay Forrester 1971 Book World Dynamics, the earlier, simpler version of the World 3 Limits to Growth Model. adapted from Mark Heffernan's ithink version at Systemswiki.

An element of Perspectives: The Foundation of Understanding and Insights for Effective Action. Register at http://www.systemswiki.org/

This model uses simple functions (converters, cosine) to simulate the water balance inside a reservoir.

In Chile, 60% of its population are exposed to levels of Particulate Matter (PM) above international standards. Air Pollution is causing 4,000 premature deaths per year, including health costs over US$8 billion.

In Chile, 60% of its population are exposed to levels of Particulate Matter (PM) above international standards. Air Pollution is causing 4,000 premature deaths per year, including health costs over US$8 billion.

This is step 2 in making a climate model based on our insights of how trees actively contribute to the cooling capcacity of the Earth.​

In this step we divide the incoming energy from the sun to the land and to the oceaan.

This model illustrates predator prey interactions using real-life data of fox and rabbit populations.

This model illustrates predator prey interactions using real-life data of wolf and moose populations on the Isle Royale. It was "cloned" from a model that InsightMaker provides to its users, at
https://insightmaker.com/insight/2068/Isle-Royale-Predator-Prey-Interactions
Thanks Scott Fortmann-Roe.

I've created a Mathematica file that replicates the model, at
http://www.nku.edu/~longa/classes/2018spring/mat375/mathematica/Moose-n-Wolf-InsightMaker.nb

It allows one to experiment with adjusting the initial number of moose and wolves on the island.

I used steepest descent in Mathematica to optimize the parameters, with my objective data being the ratio of wolves to moose. You can try my (admittedly) kludgy code, at
http://www.nku.edu/~longa/classes/2018spring/mat375/mathematica/Moose-n-Wolf-InsightMaker-BestFit.nb

{WolfBirthRateFactorStart,
WolfDeathRateStart,
MooseBirthRateStart,
MooseDeathRateFactorStart,
moStart,
woStart} =
{0.000267409,
0.239821,
0.269755,
0.0113679,
591,
23.};

Marine plastic is rapidly increasing due to increasing production and use of plastic in all economic activities, short use times and long life times of plastic, and large mismanagement of plastic waste. With this, the threat plastic poses to the marine biosphere is also increasing and will continue to increase over a long time into the future. Risk knowledge is limited and risk perception and awareness are not resulting in significant mitigation efforts. The case study will aim at modeling the use and life cycles of plastic and the transport paths that lead to plastic entering the ocean. The models will be used to simulate possible futures based on a scenario approach. The results of these efforts will be visualized with the goal to increase risk awareness.

Diagrams of theories of control of destiny at multiple scales as fundamental causes of social determinants of health from Whitehead 2016 article in Health and Place

My AP Environmental Homework for the Cats Over Borneo Assignment