Consequences and sustainable habits

The "One Health" approach links human health, animal health, and ecosystem health. Explain this using an example, such as the spread of disease-carrying mosquitoes due to rising temperatures.

Name three consequences of climate change and briefly explain one of them.

Name two consequences of climate change for people and two for nature.

Explain what a heatwave is and cite two precautions that should be taken during one.

Explain two causes of sea level rise (the melting of ice caps and glaciers, and the thermal expansion of water as it warms) and one consequence for coastal areas and islands.

Sea level rise threatens low-lying coastal areas such as the Shannon Estuary. Explain two effects it can have on that ecosystem and on the human activities carried out there.

With rising temperatures, many plants flower earlier and some birds start their migrations earlier. Explain what problem arises if flowering and the arrival of pollinating insects become out of sync.

Corals expel the algae they live with when the water gets too warm (coral bleaching) and can die. Explain what this phenomenon consists of and why the loss of a reef affects the entire marine food web.

What is carbon footprint? Name two actions from your daily life that would reduce it.

Many devices keep using electricity on standby even though they seem to be off. Name two examples from home and explain which habit avoids this consumption and how it helps the climate.

Your family wants to reduce its carbon footprint. Propose a plan with three changes (food, transport, and energy) ordered according to the emissions savings you estimate for each one, justifying the order.

The graph shows the average daily direct $\text{CO}_2$ emissions per student according to the means of transport used to travel to school.

1. a) A secondary school with 300 students who currently travel alone by private car is considering two emission-reduction measures for a school year of 180 school days:

• Option 1: Create a municipal school bus route that manages to attract 60% of those students.

• Option 2: Build a secure bicycle parking facility that gets 30% to cycle and another 20% to carpool (at a rate of 4 students per vehicle, dividing car emissions by 4).

Quantitatively calculate the total $\text{CO}_2$ savings (in kg) that would be obtained with each option and justify which one is more effective.

1. b) A classmate claims that the graph proves that cycling has zero environmental impact (0 kg of $\text{CO}_2$) under any circumstance. Refute this statement by distinguishing between direct emissions during use and indirect emissions throughout its entire life cycle.

The average annual carbon footprint of a citizen in Ireland is distributed approximately as follows: transport (2.1 t of $\text{CO}_2$), heating/cooling and electricity consumption at home (1.6 t), food (1.3 t), and consumption of manufactured goods (0.9 t).

A person sets a goal to reduce their total footprint by at least 20 % in one year and is hesitating between two independent alternatives:

• Alternative A: Replace all light bulbs with state-of-the-art LEDs and always turn off appliances on standby, achieving a 10 % reduction in home energy consumption.

• Alternative B: Replace their private vehicle with public transport and a bicycle for their regular commutes, reducing their transport impact by 40 %.

1. a) Calculate the baseline footprint and verify quantitatively whether either of the two alternatives allows reaching the 20 % target.
2. b) Many people believe that acting only on domestic electricity savings is enough. Based on the numerical results, justify why having an impact on transport and diet is quantitatively much more decisive in curbing global warming.

Order the three Rs — recycle, reduce, and reuse — according to their environmental priority and give an everyday example of each.

State which bin each item of waste should go in and explain why separating them is important: a glass bottle, a battery, a banana peel, a can, and a plastic bag.

Explain what responsible consumption is and give an example of a sustainable purchasing decision.

Your secondary school wants to become more sustainable. Propose three specific measures (one regarding energy, one regarding transport, and one regarding waste) and justify each one.

Composting organic waste prevents it from decomposing in landfill and releasing methane, and it also produces natural fertiliser. Explain this double benefit for the climate and for the soil.

In the municipal plenary session of a town of 4 000 inhabitants, the budget to install community composters and pedestrian lanes is being debated. A councilor argues: "Our emissions are 0.001 % of those of the region; if large metropolises do not act, whatever we do here is a waste of money that will not alter the global climate."

1. a) Refute the councilor's stance by applying the motto "Think globally, act locally", using the concepts of ecological co-responsibility and multiplier effect.
2. b) Describe in detail the biological or physical mechanism by which collecting and composting organic waste instead of depositing it in a conventional landfill prevents the emission of a potent greenhouse gas into the atmosphere.