A snippet that load data from Ajax once the store it in session storage, then use it from session storage for future calls.

session-storage-ajax.js

/**
* load the content via AJAX,
* and attempt to cache in sessionStorage
*/
(function() {
 
    var hasStorage = ("sessionStorage" in window && window.sessionStorage),
        storageKey = "yourUniqueStorageKey",
        now, expiration, data = false;
 
    try {
        if (hasStorage) {
            data = sessionStorage.getItem(storageKey);
            if (data) {
                // extract saved object from JSON encoded string
                data = JSON.parse(data);
 
                // calculate expiration time for content,
                // to force periodic refresh after 30 minutes
                now = new Date();
                expiration = new Date(data.timestamp);
                expiration.setMinutes(expiration.getMinutes() + 30);
 
                // ditch the content if too old
                if (now.getTime() > expiration.getTime()) {
                    data = false;
                    sessionStorage.removeItem(storageKey);
                }
            }
        }
    }
    catch (e) {
        data = false;
    }
 
    if (data) {
        // load data from session storage
        showContent(data.content);
    }
    else {
        // fallback to AJAX loader
        jQuery.ajax({
            type : "GET",
            url : your_ajax_url,
            dataType : "html",
            data : { action: "your-ajax-action" },
            success : function(content, status, xhr) {
                // save in session storage if available
                if (hasStorage) {
                    try {
                        sessionStorage.setItem(storageKey, JSON.stringify({
                            timestamp: new Date(),
                            content: content
                        }));
                    }
                    catch (e) {
                        // silently suppress, it doesn't really matter
                    }
                }
 
                // show the new content
                showContent(content);
            }
        });
    }
})();
 
/**
* your function for displaying the content
* @param {String} content
*/
function showContent(content) {
    // your code here...
}