Assignment 1 - Fall 2023

GEOL 106 ASSIGNMENT 1 – CLIMATE CHANGE THROUGH TIME Due Date: Sept 28* (11:59 PM, Kingston time) Mark: /20 ________________________________________________________________________________________ A few things before starting. • I provide an answer sheet (in Word format) where you can write your answers. Please use this sheet, it makes it easier for the TAs to be consistent in their marking. • answer sheet can be upload in OnQ; save as a PDF or in Word , TAs can’t always open Pages. • information I give you to read through prior to the questions can be useful. * with the 3-day grace period, date is Oct 1 1. Which point is older? Point A or Point B? (1 mark) Point A is older, as it is further along the graph about 350,000 years old. 2. What variable does the Y-axis show? (1 mark) The Y-axis represents the temperature in degrees Celsius compared to the modern average. 3. Does 0°C on the Y-axis corresponding to the freezing point of water? If not, explain what 0°C on the Y-axis represents? ( 2 marks ) It doesn’t correspond to the freezing point of water, it represents the current average, as said on the graph. 4. Briefly describe what you see; are there any trends (if any) that you observe? ( 1 mark ) Over every 100,000 to 150,000-year interval, there is a peak in the temperature at 2 degrees Celsius. 5. Does the Earth enter into glacial intervals in the same manner that it enters into interglacial intervals? ( 1 mark ) Briefly describe what you see. ( 1 mark ) No, they don’t occur in the same manner. Based on the information provided, it’s clear that the transitions between glacial and interglacial intervals, as depicted in the graph, are gradual processes. These transitions unfold over extended periods, potentially spanning thousands of years. Notably, the graph illustrates a significant number of interglacial intervals where temperatures rise above a specific threshold (above -6 degrees Celsius). 6. What was the ~ atmospheric CO 2 concentration 350,000 years ago? ( 1 mark ) The atmospheric CO 2 concentration was 180ppm. 7. Do times of low atmospheric CO 2 on the carbon dioxide graph correspond to the times of cooler temperatures seen on the age vs temperature graph? Why do you think this is? ( 2 marks ) Yes, they do portray a similar pattern. This is usually because of how certain gases such as CO2 get trapped in the Ear th’s atmosphere. When CO2 levels in the atmosphere are low, there are fewer greenhouse gases to trap, hence leading to a cooler climate and vice versa as shown in the graph. 8. Was the Earth in a glacial or interglacial interval at this time? ( 1 mark ) 350,000 years ago, Earth was experiencing a glacial interval at this time. 9. Is there similarity among the temperature curves from the different locations? ( 1 mark ) There is some similarity between the temperature curves from Vostok ice cores in Antarctica and Greenland, however there is no similarity show in the salt cores in California or Chile. 10. If so, which cores generally match up? ( 1 mark ) The ice cores generally match up. 11. Which one(s) seem to reflect a different palaeoclimate history than the others? ( 1 mark ) Atacama salt core seems to reflect the most different paleoclimate history. 12. Which cores might reflect global climate trends more than local climate trends? ( 1 mark ) The Vostok ice and GRIP ice core in Greenland and specifically Antarctica are considered to be more representative of global climate trends, as Antarctica’s climate is less influenced by regional and local factors due to it being an isolated location. 13. Do you think one core alone can provide good palaeoclimate data? ( 1 mark ) Yes, the Vostok ice core. 14. Report the current atmospheric CO 2 concentration and the date. ( 1 mark )