We already know that global warming is making the planet hotter. Scientific studies have also shown that our changing climate could favor the formation of more ozone pollution in some areas and also intensify the health problems stemming from allergenic pollen such as ragweed. This is bad news for allergy sufferers and asthmatics because both ragweed and ozone have been linked to respiratory problems such as asthma and to allergic symptoms in adults and children. Moreover, studies show that people exposed to both ragweed and ozone can become sicker than people exposed to just one of these pollutants. These negative health effects will only get worse if carbon dioxide (CO2) concentrations keep rising and global warming continues unchecked.