C264 Climate Change

Explanation:

If present warming trends persist, Arctic sea ice will continue to decline in both summer and winter, though the summer minimum will remain the most dramatic. The loss of reflective ice amplifies warming through the ice–albedo feedback, which allows more solar energy to be absorbed by the darker ocean. This continuing reduction in ice cover will likely disrupt global climate systems by altering the jet stream, affecting mid-latitude weather, and contributing to sea-level rise through interactions with Greenland’s ice sheet.

Correct Answer:

The reduction in sea ice will likely become more pronounced in both summer and winter, potentially disrupting global weather patterns.

Why Other Options Are Wrong:

Sea ice will increase in winter and decrease in summer, stabilizing global temperatures. Observations and models consistently show winter ice extent shrinking over time, not increasing. Warmer ocean and air temperatures prevent the refreezing necessary for winter growth, and any idea of stabilizing global temperatures contradicts current scientific consensus that continued greenhouse gas emissions will enhance warming and destabilize climate patterns.

There will be no change in seasonal patterns, as climate change does not affect the Arctic. The Arctic is warming at more than twice the global rate, a phenomenon known as polar amplification. Satellite data show unmistakable downward trends in both summer minimum and winter maximum ice extents. Claiming no change denies the overwhelming evidence from decades of direct measurement and sophisticated climate modeling.

Sea ice will only decrease in winter, leading to cooler global temperatures. Sea ice loss is greatest in summer, though winter ice is also declining. Additionally, reduced sea ice leads to greater heat absorption and overall planetary warming, not cooling. This option misrepresents both the seasonality of ice decline and the resulting climate feedbacks, which drive further warming rather than a cooler global climate.

Explanation:

Weather satellites are crucial for monitoring the atmosphere on a global scale. They provide continuous, real-time data on cloud patterns, storm development, precipitation, and other atmospheric phenomena. This information allows meteorologists to track and predict weather events, study storm intensity, and improve forecasting models. Satellites complement ground-based observations by offering a broad perspective that is not limited to specific locations, helping scientists understand large-scale atmospheric dynamics.

Correct Answer:

They provide real-time data on cloud cover and storm systems.

Why Other Options Are Wrong:

They measure ground temperature directly.

Satellites primarily measure radiative signals from the atmosphere and surface, but they do not provide direct contact measurements of ground temperature. Ground thermometers and weather stations are needed for direct temperature readings.

They only track temperature changes at the surface.

This is incorrect because satellites monitor many aspects of the atmosphere, including cloud cover, storm systems, moisture levels, and upper-atmosphere temperatures, not just surface temperature.

They are used solely for predicting long-term climate trends.

Satellites provide valuable data for both short-term weather forecasting and long-term climate studies, so their function is not limited to long-term trends alone. Limiting their role to climate prediction overlooks their real-time operational importance.

Explanation:

Satellite measurements from NASA’s GRACE (Gravity Recovery and Climate Experiment) and follow-up missions show that the Greenland ice sheet has been losing ice at an accelerating rate since the early 2000s. Cumulative losses from 2002 through the mid-2010s to early 2020s are estimated at roughly 4,000 gigatons (Gt) of ice. This massive loss contributes directly to global sea level rise and reflects the sensitivity of the Greenland ice sheet to warming air and ocean temperatures.

Correct Answer:

4,000 Gt

Why Other Options Are Wrong:

2,500 Gt

This underestimates the observed loss, which exceeds this value according to long-term satellite data.

6,500 Gt

This is higher than current published estimates for the period since 2002, so it overstates the measured loss.

1,000 Gt

This is far too low and does not reflect the substantial and well-documented mass loss from Greenland in the past two decades.

Explanation:

Each spring, as temperatures rise and daylight lengthens across the vast forests and grasslands of the Northern Hemisphere, plants undergo a surge of photosynthesis. This process draws in large amounts of atmospheric CO2, temporarily lowering global CO2 concentrations until plant activity slows in autumn and winter. The seasonal “breathing” of the biosphere creates a distinct annual cycle in atmospheric CO2 records, with concentrations dipping during the growing season.

Correct Answer:

Increased photosynthesis during spring growth

Why Other Options Are Wrong:

Decreased sunlight during winter months. Winter darkness contributes to a seasonal CO2 increase, not a decrease, because photosynthesis slows and respiration continues, allowing CO2 to build up. Reduced sunlight is therefore associated with rising, not falling, CO2 levels.

Increased volcanic activity. Volcanic eruptions typically emit CO2 rather than remove it, and their sporadic timing cannot account for the regular, predictable seasonal decline in atmospheric CO2 observed every spring and summer.

Decreased plant growth in summer. Summer is when plant growth and photosynthesis peak in much of the Northern Hemisphere, leading to maximum CO2 uptake. A decrease in summer growth would reduce this uptake and cause higher CO2, the opposite of the observed seasonal decline.

Explanation:

While global temperatures are rising overall, specific regions such as parts of the North Atlantic and waters near Antarctica have shown localized cooling. This pattern is largely due to the influx of cold, fresh meltwater from Greenland and Antarctic ice sheets. The fresh meltwater not only cools the surrounding ocean surface but also can disrupt ocean circulation patterns, like the Atlantic Meridional Overturning Circulation, further reinforcing regional cooling despite the global warming trend.

Correct Answer:

Melting ice sheets in Greenland and Antarctica keep those waters colder

Why Other Options Are Wrong:

Because the general predictions of global warming are uncertain

Scientific predictions of global warming do account for regional variations. The localized cooling is not due to uncertainty in climate models but to known mechanisms like ice melt and ocean circulation changes.

Ocean currents in those areas kept things cooler

While ocean currents play a role, the key driver of the specific cooling trend is the input of cold freshwater from melting ice sheets, not simply normal current patterns.

Atmospheric jet streams isolate cold pockets in those areas

Jet streams influence weather patterns, but they do not explain the long-term regional ocean cooling observed near Greenland and Antarctica.

Explanation:

Comprehensive satellite observations began in 2002 with the launch of NASA’s GRACE (Gravity Recovery and Climate Experiment) mission. These satellites provided precise measurements of changes in the mass of the Greenland and Antarctic ice sheets, revealing a consistent and accelerating trend of ice loss from that point onward. While some evidence of earlier melting exists from field studies, 2002 marks the start of continuous, global-scale monitoring that conclusively documents their sustained melt.

Correct Answer:

2002

Why Other Options Are Wrong:

1990. Although some regional studies detected signs of ice loss before the 2000s, there was no comprehensive, high-precision satellite monitoring of total ice sheet mass in 1990. The ability to measure widespread melting with confidence began later with dedicated satellite missions, so 1990 cannot be cited as the definitive observational start.

2000. By 2000, satellite technology had advanced, but systematic, large-scale measurements of the ice sheets’ mass changes were not yet in place. Observations before 2002 lacked the resolution and global coverage needed to accurately quantify melt rates, making 2000 premature for reliable, continuous records.

2010. Waiting until 2010 overlooks nearly a decade of confirmed data showing substantial mass loss in both Greenland and Antarctica. GRACE satellites had already documented significant melting trends well before 2010, so this date understates the length and extent of observed ice sheet decline.

Explanation:

Climate change impacts are not evenly distributed; some regions, such as the Arctic or low-lying island nations, experience much more dramatic and immediate effects than others. Areas with slower or less visible changes may create a false impression that global changes are minimal. This uneven distribution means people in less-affected regions may underestimate the urgency or extent of global climate change.

Correct Answer:

Some regions experience more dramatic changes than others.

Why Other Options Are Wrong:

Changes are uniform across all regions.

This is incorrect because scientific evidence shows that warming, sea level rise, and ecosystem impacts vary widely across the planet. For example, polar regions are warming at roughly twice the global average, while some equatorial regions see smaller temperature changes.

People are not interested in climate change.

While public interest and awareness vary, the lack of recognition is not simply due to disinterest. Many people are concerned about climate change but may not observe dramatic local changes, making this answer too simplistic and inaccurate.

The changes are only visible from space.

Climate-related changes can be observed on the ground—such as shrinking glaciers, shifting plant and animal ranges, and more intense storms—without requiring a view from space. Satellite imagery helps track global trends but is not the only way to detect climate change effects.

Explanation:

Sea level rise results primarily from the melting of land-based ice, because this adds water to the ocean. The Greenland Ice Sheet and the West Antarctic Ice Sheet are the two major ice masses currently contributing significantly to global sea level rise. In contrast, Arctic sea ice floats on the ocean and its melting does not directly raise sea level, and the other listed glaciers or ice features are either too small or geographically irrelevant to contribute meaningfully on a global scale.

Correct Answer:

The West Antarctic and Greenland Ice Sheet

Why Other Options Are Wrong:

Arctic Sea Ice and African Ice Core

Melting sea ice does not appreciably raise sea level because it is already floating, and African ice cores are small and insignificant contributors compared to the vast polar ice sheets.

Gangotri glacier and Kangchejunga ice sheet

These Himalayan glaciers are much smaller and while they affect regional water supplies, they are not major drivers of global sea level rise.

Rocky Mountain Ice Pack and frozen Niagara Falls

These represent minor or seasonal ice formations that do not significantly contribute to global sea level changes.

All of the above

This is incorrect because only the Greenland and West Antarctic ice sheets are large enough and currently melting at rates that meaningfully raise global sea levels.

Explanation:

The Amihan is the cool northeast monsoon that brings dry winds to the Philippines. It typically begins around late October or early November and lasts until about April, dominating the country’s weather during the cooler, drier season. This pattern is well documented in Philippine meteorology and is associated with winds originating from the northeast that bring lower humidity and relatively cooler temperatures compared to the wet southwest monsoon (Habagat).

Correct Answer:

November to April

Why Other Options Are Wrong:

May to October. This period corresponds to the Habagat, the southwest monsoon that brings warm, moist air and heavy rainfall, the opposite of the cool, dry Amihan conditions. Associating Amihan with this wet season ignores the established timing of monsoon patterns in the Philippines.

January to June. Although January through April falls within the Amihan season, extending it to June is inaccurate because by May the southwest monsoon is already beginning to dominate, shifting winds and increasing rainfall.

July to December. The early part of this span (July to October) is firmly within the Habagat rainy season. While November and December mark the onset of Amihan, placing the entire range from July is misleading and does not match the climatological record.