As El Nino rolls out in the Northern Hemisphere and dumps lots of rain, pockets of agriculture already are getting hit. El Nino-related precipitation has caused some mudslides and erosion. And storms across the Southwest have hurt dairy cattle inventories in Texas and New Mexico.
Now some food transportation on barges is slowing as El Nino-related rain has ballooned rivers. "Swelled major waterways across the nation have slowed the movement of barges, which are an important channel for the distribution of agricultural goods," according to an El Nino economic report from IHS Global Insight, released this month.
"Delays are still going on," said Ryland Maltsbarger, an agricultural economist at IHS. "We're having to limit traffic, especially with barges," he said.
Plumped waterways are impacting some barge traffic in and around the Midwest down to the Gulf Coast, and involves such channels as the Mississippi River, Maltsbarger said. Crops and food impacted so far include corn, soybeans and fertilizer, which is used in nearly every pocket of food production.
"For now it's short-term impact," said Maltsbarger. Other floods in recent years have led to widespread river closures that impacted, for example, the movement of grains, according to IHS research.
"If we move into the spring and we get these increased rains, it will have a much bigger impact," Maltsbarger said. "There's prime farmland along the rivers that could get flooded."
The fact that barges are even used for shipment of agricultural goods may come as a surprise. But hauling goods on waterways — everything from coal to grains — predates America's railroads, and can cost a fraction compared to shipping goods by rail.
Specifically for the delivery of agricultural products, barges today are the equivalent of massive, steel bathtubs and are the second-biggest transportation mode behind railroads, said Charles Clowdis, managing director of transportation at IHS. "Barges are a very dependable type of transportation," he said.
Taking into account El Nino's impact on multiple sectors, including agriculture, the overall net effect of El Nino typically is small but positive. The economic benefits of the 1997–98 El Nino event — the most severe to date — were about 0.2 to 0.5 percent of GDP. IHS expects impacts on the same order of magnitude during the 2015–16 El Nino.
The current El Nino is forecast to affect temperature and precipitation patterns across the U.S. in the coming months. There's an "increased likelihood of above-median precipitation across the southern tier of the United States, and below-median precipitation over the northern tier of the United States," according to the National Weather Service.
Of course, the blessings of more rain triggered by El Nino can bring other consequences. California almond farmers, for example, already are talking about how El Nino-triggered wet and cold might dampen pollination activity, and potentially trigger lower crop yields.
In crops, including almonds, apples and cherries, bees travel from blossom to blossom for food. In the process, they spread pollen containing the male sex cells, which enables the plant to bear fruit. But bees can stay in their hives when it's cold and rainy instead of making their pollinating rounds.
"Usually, honey bees do not forage when the temperature fails to reach 55 degrees Fahrenheit, the wind exceeds 12 miles per hour, or it is very foggy, rainy, or the flowers are damp," said Eric Mussen, an expert in bee management at the University of California Davis. But all is not lost yet.
"A good commercial crop is set with less than 50 percent of the blossoms turning into nuts," said Mussen in an email to CNBC. "So, if the bees can have a few hours, every so often, to get to the blossoms, there will be almond pollination," he said.
The naturally occurring weather trend known as El Nino also is happening amid climate change.
That means El Nino's impacts could be less predictable and more severe, according to Stephen O'Brien, U.N. under-secretary-general for the coordination of humanitarian affairs. He made the prepared remarks earlier this month.
O'Brien said in some global regions, millions of people are already facing food insecurity caused by droughts related to El Nino. "The impacts, especially on food security, may last as long as two years," he said, expressing particular concern about a number of countries spread across Central and South America, the Pacific region and East, and southern Africa.
Some regions face potentially devastating effects on the agricultural sector, including floods, landslides and droughts, possibly leading to forest fires, according to the U.N.
Climate change has led to fire seasons that are now on average 78 days longer than in 1970, according to a report on the rising cost of wildfire operations from the U.S. government last year. The six worst fire seasons since 1960 have all occurred since 2000, according to the report.
More than 100 years ago, President Theodore Roosevelt created the U.S. Forest Service to manage America's 193 million acres of national forests and grasslands. Today more than 50 percent of the Forest Service's annual budget is dedicated to wildfires, versus just 16 percent in 1995, according to the report.
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