Properties of pollen
What is the connection between pollen and climate change? All flowering plants produce pollen grains and their distinctive shapes can be used to identify the type of plant from which they come. Since pollen grains are well preserved in the sediment layers at the bottom of ponds, lakes or oceans, an analysis of the pollen grains in each layer can tell us what kinds of plants were growing at the time the sediment was deposited. Pollen and spores are critical elements in the lifecycle of vascular plants. Because they have very resistant walls, pollen and spores are typically the most abundant, easily identifiable and best-preserved plant remains in sediment and sedimentary rocks.
The changing climate
The severity of allergies and asthma is closely linked to environmental conditions, particularly air quality. Climate change and rising levels of CO2 are projected to worsen air quality and could threaten human health in many areas due to increased levels of allergenic pollen and ground-level ozone. Scientific studies have found that allergenic pollen production increases as CO2 concentrations rise and temperatures climb. Ragweed plants, for example, have been shown to grow bigger and produce more pollen when levels of CO2 increase, and to produce pollen over a longer season. These plants have also shown increased tolerance to high ozone levels.
Many of the sources of ozone-producing chemicals — industrial facilities, electric power plants and motor vehicles — also emit the carbon pollution that is driving climate change. Minimising emissions from these sources can therefore help to reduce ozone pollution and climate change, helping to create better air quality today and a cooler, healthier environment in the future.